RaWarrior
Well-Known Member
Did someone ask for a new-owner FAQ?
Here at VMF, we love new members, those of you brave enough to welcome a V-max into your garage, and the pet mod-monkeys that tend to nest somewhere between the rear head and fuel tank. We realize new owners are going to have a lot of questions, since the Vmax does have some unique/unusual features, as well as several quirks that may puzzle the new owner. While everyone here wants to help, several questions come up again and again with frankly annoying frequency. Which isn't your fault in the slightest, but it's time we compile all these "noob FAQs" into a single document. It'll hopefully answer many if not all of your new-to-me bike questions in one fell swoop. Hopefully this will be around for millenia worth of vmax owners, if a mod stickies it somehwere.
I'll preface this by saying/admitting that I am cheap. I don't mind spending money when it's needed, but I hate over-paying when it's simply not needed or just overkill. I don't believe in "whatever costs the most is the best" or "if some is good more is better". The couple suggestions given in this article are for products that I feel are a good value and that in my experience perform just as well if not better than more expensive/"premium" brands. Feel free to ignore them.
Section 1: Oil
1. I just got my bike, and want to change the oil in it. Which oil is best to use?
This is probably the single most frequently asked question, so here's the short answer:
Any oil is fine, so long as it doesn't say "high mileage" or "energy conserving". These contain friction modifiers that can cause clutch slippage.
2. Should I use conventional (dino oil), or synthetic? Do I need motorcycle-specific oils?
This is another "area of personal preference". Yamaha did not specify or require any sort of synthetic lubricants and almost universally oils on store shelves now are far better than they were in 1985. The oil spec Yamaha called for(a normal automotive spec) has been long superseded. It is entirely up to you, and in reality, will make very little difference. Your riding style and maintenance habits have far more effect on engine life than does whether or not you sprung for that expensive synthetic or not.
That said, I personally feel that top shelf synthetics are not ideal for the Vmax. Full synthetics have been associated with clutch slippage(especially with the marginal stock clutch spring), and I can attest they can cause starter clutch issues(mine would often fail to "catch" in cool weather with full syn, after switching to rotella, it's never missed again). It's also not uncommon for an engine to be oil-tight, then develop a leak shortly after the oil is changed to synthetic especially on older motors, or ones that have been resealed with a liquid gasket rather than a real one. While you can argue the "correct" solution is to replace the gasket, in many cases you would rather just avoid the problem in the first place.
Do you need motorcycle specific oils? No. People have well over 100k on their original engines using nothing but plain old car oil. Will it hurt? No. So once again, your taste and budget should dictate.
So, my personal suggestion would be to stick with a conventional oil. Take it with a grain of sand.
3. Come on, any suggestions? I'm critically indecisive and can't pick an oil.
Many members here use Shell Rotella-T conventional 15-40. It's a heavy duty (aka diesel) oil, which has more ZDDP(an extreme pressure zinc lubricant). I noticed it smoothed out shifting and made neutral easier to find over Mobil 1 full synthetic. There are NO problems with using "diesel" oil in a gas engine. It comes in 1 gallon jugs, which are $13 at wal-mart. Your bike takes around 3.5 quarts, you'll have a little left over for your lawnmower or something. It's proven, cheap, and very easy to find, virtually any place that sells motor oil has it.
4. What weight should I use?
Yamaha specified 10w-40, same as pretty much every other wet clutch engine out there. To really understand this (and it's a lot more complex than most people think), I'd suggest you read through this.
It's several pages, but has a lot of good info and explains the subject in depth. Still, here's the sparknotes version.
The first number reflects the oil's viscosity, or "weight", with a cold engine, and the second number is for the oil at operating temperature (lets say ~200* F). It's widely stated that 90% of engine wear occurs at startup, so it only makes sense that we focus our oil choice on preventing this startup wear. A 0W-30 oil gives the same hot engine protection as a 10-30, but will reduce wear at startup by flowing quicker and easier. There's also some misconceptions about oil pressure, with a notion that more is better. While it's certainly bad if you have zero across the board, keep in mind pressure is defined as a "resistance to flow". This is why pressure is very high on a cold engine, the oil is very resistant to flowing, and it falls off as it warms. Oil flow is much more important than pressure, more flow means more lubrication and more cooling. Zero indicated pressure on a hot idle does NOT mean that no oil is flowing, but rather that it is flowing with almost no resistance, and shouldn't be any cause for concern. Even in the owner's manual of my Z is says it's "no cause for concern" if the oil pressure light comes on at idle, so long as it goes off again once RPMs are raised. But the old conventional wisdom says that very thin oil does not "cushion" between parts as well and will not protect as well. Simply put, this isn't true. Thicker "hot" oils can help to quiet a tired, loose engine, or an older mill with greater tolerances. For modern engines(and you can call the Vmax modern), this thicker oil needs more force to squeeze it through the tight tolerances and smaller galleys, which raises pressure and saps energy from the engine.
But what about hot climates? "I live in Florida and frequently have to ride in stop-and-go traffic where the engine gets very hot." Again, your coolant gets hot due to the lack of airflow, hindering the radiator's ability to get rid of the heat. The oil will get a little warmer, but idling in traffic has the engine under little to no load at low RPMs, and a thicker oil would not help it cool better (to the contrary, it flows and circulates less, transferring less heat from the parts).
So, what to use? Yamaha says 10-40, but you're suggesting that thinner is better.
Here's where it's up to you. People like to tout they've "never had any problems" with Brand X oil of their choice, therefore it is a good oil. Frankly, engine failures due to a poor quality oil are virtually unheard of these days, so that's not a very good argument. Specifically to motorcycles, some brands of oil do have noticeable effects on shift action, clutch wear and clutch drag. Neutral being difficult to find is a sign the clutch is dragging more, from a less slippery oil (or clutch problems, but we'll assume it's in good order). I have used 10-40, 15-40, and recently 0-30 in various bikes I've owned. While I sold my Vmax last summer and can't give a direct comparison on that, I did change on my Z, from the 15-40 Rotella conventional to the 5w-40 Rotella T6 synthetic Cold cranking is faster and easier, and the motor is quieter in the few seconds after startup. Shift action is lighter and easier as well, which does back up what "Bob the Oil Guy" claims.
So the conclusion is that really any oil is suitable, and short of pouring 50w in for dead winters of Alaska, will not cause problems. Long term wear can be minimized by using a thinner multi-grade oil of either conventional or synthetic. Synthetics have better flow characteristics than a conventional of an equal grade, and have longer service intervals (many new bikes specify 7500 or more miles between changes). Of course, synthetics cost 2-3x more.
You're armed with the info, now make your own choice.
5. How often should I change it?
How ever often helps you sleep at night. To me, any more often than every 3000mi is just wasting perfectly good oil, assuming normal street riding, but excessive oil changing never hurt anything, so if you want to, go for it. My trick for the Vmax (and this is just a personal observation), is to change it when neutral starts getting hard to find, meaning the clutch is dragging more than it used to. I usually did every 5k miles, and scheduled them on the 5's....so 20,000 miles, 25k, 30k, ect, keeps it easy to remember. If you use your bike on the strip or track regularly, more frequent changes are advisable.
6. What about filters?
For 85-95 bikes, you take a cartridge style filter, and don't have a ton of choices. Fram CH6002, OEM Yamaha, or a generic aftermarket.
For 96-07 bikes, you take a spin-on style, and have loads of choices. Fram PH6017, Purolator ML16817, NAPA Gold 1358 are all MC-specific filters. Some members reference a Bosch 3323 automotive filter as well. Note that the 3323 is too long for use with Hindle headers, though the shorter 3330 does fit.
A "top shelf" choice is a K&N filter. Part # KN303. They're commonly found in black, but some stores carry the chrome versions as well. Otherwise you can get them on ebay if you want the shiny.
There are also stainless mesh reusable filters out there, but they're around $100. PC Racing's "FLO" filter is fairly common.
Stick a couple small puck magnets to the outside of the filter, if you cut it open when you change you'll see a big glob of nasty collected on top of where the magnet was. You can get a pack of these at any hardware store for like a dollar.
It can be noted that Bosch, Mobil1, and Supertech (wal-mart) are all made by Champion Labs, the only difference is the filter media. NAPA Gold and Carquest Premium are identical to (and made by) WIX.
Fram filters have a lot of evidence against them, and if you poke around you can find lots of horror stories related to their failure. They're built with cost, not quality in mind. While I'd consider some of the tales out there definitely to be exceptions rather than the norm, higher quality filters are only a dollar or two more expensive, so why compromise?
7. I want to read 30+ pages of oil-related discussion. Can you help?
Sure! Click here.
Section 2: Tires
8. Which tires are best for the Vmax?
From popular vote, there seems to be two favorites. Your budget and riding style should dictate:
Metzeler Marathon ME880.
+Good tread life...8-10k if you don't burn out at every stoplight.
+Excellent handling. Far improved over stock Dunlops
+High quality...balance easily
-Expensive
-Not as sticky as Shinkos
*Note: The ME880 now has the ME888 Marathon Ultra version as well. The 888's are available in the 170 rear for the vmax, but not in a size that fits the front.
Shinko Tourmaster T230
+Cheap. Cost about 60% of what the Metzelers do.
+Very sticky. Superb traction.
-Wear very quickly...often done in only a couple thousand miles
-Taiwanese quality, or lack thereof. Often need loads of weight to balance, and have been known to wear poorly/unevenly.
9. Can I put bigger tires on my Vmax?
Yes. Both the above tires are made in the Vmax stock size (bias ply)
110/90-18 front
150/90-15 rear
as well as the "bigger" options
120/80-18 front (120/90-18 for the Shinko)
170/80-15 rear
Larger than that requires aftermarket rims. The 170 rear tire swap is very popular, and the 170 rear is typically cheaper as well since the 150 is considered a "specialty" size and the 170 is more widely used. Switching to the 120 front will throw off your speedometer, and is not as widely done. It is possible to put a radial tire on the front rim, but nobody makes 15" radial tires, and mixing bias and radial tires is not recommended.
10. What do the tire size #'s mean?
Width/aspect ratio- rim diameter
For example, 110/90-18 means the tire is 110mm wide, is 90% as tall(profile) as it is wide, and is for an 18" rim.
Section 3: Controls/cockpit (giggle now.....)
11. Whats that "whirr-WHIRR"/ clicking noise I hear every time I turn the key on(or flip the kill switch to run)?
That is your v-boost servo self-testing itself. It is perfectly normal. It opens, then closes the valves to let you know it's working. It is controlled by the engine's computer, and opens them around 6000RPM. It gives the same effect as a 4-barrel carb opening the second two at full throttle, however they are controlled by RPM, not throttle position. This is the "whirr-whirr". The "clicking" is the fuel pump topping up the carb bowls. It should click rapidly, and then slow to a stop as the bowls fill. If it constantly clicks(runs) rapidly, or does not slow/stop after a couple key cycles, you could have a bad fuel pump(or a fuel line leak, or leaky needle/seat).
12. What's the deal with the fuel light and reserve switch? How's that work?
The Vmax has a sensor in the tank, set so a small filament is placed corresponding to the level of about .9 gallons left. At all times, current is passed through the filament, but the gasoline acts as a heat sink and prevents it from heating up. When the filament it cool, it has a very high resistance. When the fuel level drops below the filament, it begins to heat up. As it warms, it's resistance drops and power is slowly allowed through...why the fuel light slowly fades on, and never gets very bright. This also trips a relay that shuts off power to the fuel pump...this is Yamaha's way of simulating an actual reserve valve, and to ensure the bike "gets your attention" should you miss the fuel light(the bike will start to spit and sputter a minute or two after you see the light). Flipping the switch to "res" simply restores power to the fuel pump and allows the rest of the tank to be used. It should be noted to always leave this in the "on" position except when needed. Otherwise, you will get no noticeable warning(other than the dim fuel light, which is very easy to miss in bright daylight) until you are completely out of fuel.
13. I've noticed my oil light comes on or flickers under acceleration.
Perfectly normal, and nothing to worry about. Yamaha is stuck on putting oil level sensors on it's bikes, instead of a pressure sensor like everything else has. They also put it in the front of the pan(the oil pump pickup is thankfully in the rear). Under acceleration, the oil sloshes to the back, the sensor is momentarily dry, and the light comes on. As long as the oil is to the upper hashmark in the sight glass, you're fine.
14. Does the Vmax have a rev limiter at the redline?
No, it doesn't. Be careful. This motor does not tolerate over-revving well. An aftermarket Dyna ignition can add this feature, many people install a shift light on the speedometer to help prevent accidental over-revving.
15. My temp gauge hovers near the red zone when in traffic....is this a problem?
Close to the red zone is normal...the fan kicks on at 220*, which corresponds to slightly shy of the red line on the gauge. So long as it doesn't go into the red, you should be OK. It's fairly popular to add a manual fan override switch, to turn the fan on earlier(a switch that simply shorts together the two wires going to the fan switch), or swap out the stock fan thermo switch with one from a '88 Nissan Sentra, which trips the fan at like 190* or something. Your call.
16.160mph speedometer....how fast does the Vmax actually go?
With absolutely ideal conditions, about 150 mph, which corresponds to redline in fifth gear. Actually reaching this speed requires a very smooth, long road and a pair that clank. This bike is not particularly known for it's high speed stability and is fairly prone to headshake/wobbles. If you decide to venture above posted speed limits (on closed circuits only, obviously) do so with caution. Cover the rear brake and use your lower body to support your torso- don't death grip the handlebars as this can cause instability. If you do feel shudder/shakes coming on, gradually roll off the throttle and smoothly apply the rear brake only to scrub off speed until it stabilizes. A panic stab at the front brake or other abrupt maneuvers can cause a full on tank slapper. You might notice pushing the handlebars away from you tends to make wiggles and shakes go away. DO NOT do this. I repeat, DO NOT EVER do this. Without getting into a long explanation, you temporarily mask symptoms of an imbalance, while that imbalance grows with more speed, that can suddenly and violently manifest. Meaning: instant tank slapper. Instant crash. Handlebar being wrenched so hard it breaks your wrist. I can't stress this enough- DON'T.
Personally, with a Venture final drive, stock power output, and my 190lb *** onboard, I would see 140-142 or so on flat ground. I nudged 145 with a bit of a downhill. Your results may vary.
17. My speedometer needle jiggles or "bounces", what's wrong?
Most likely a sticky cable. Remove the speedometer cable at the wheel and blast wd40 or PB Blaster(which seems to penetrate faster) both into the drive, and the cable. Remove it at the speedometer(requires a bit of digging, but not bad), and do the same. Spray lube, let it soak down a bit, spray again. Do this several times, then put it back on and go for a drive. More than likely the needle will be smooth.
18. What is the expected range/ MPG of this bike?
If your bike is running well, and you don't use v-boost too too often, you should see at least 100 miles to the fuel light. A general average from members here is usually 110-120 miles to the light. From the light, you've got a bit less than a gallon left. I wouldn't push it any farther than 20 miles on reserve. Vmax is a heavy bike, not fun to push.
For MPG, that works out to high 30's to low 40's. Mine usually returned right around 38-39mpg on average.
19. Is there anything I can do to improve my mileage?
Assuming your motor is running well and carbs in good shape, you can swap in a Venture final drive. This will lower your RPMs across the board by 10% and net you an extra couple MPGs, at the expense of some acceleration. Sean Morley can give you an overdrive 5th gear as well, though it involves pulling the motor and splitting the cases, so probably best to do if you've got it apart for some other reason also.
20. Do I need the seat bolts?
No. Remove all 4 and toss them. The seat cannot come off when the fuel door is clipped down. This just saves time to get at the battery, fuses, ect.
21. How do I put gas in the damn thing?
Reach under the seat on either side, just in front of the top of the rear shocks. There are two little black levers. Press both forward at the same time and the seat's hump will flip forward to reveal the gas cap.
Section 4: Motor/Carbs
22. How powerful is the Vmax?
All years 85-07, are 145hp (at the crank). Rear-wheel HP(what actually matters) is around 115 for a stock bike in good tune. A full exhaust system(not just slip ons) and good jetting can add 10+hp to your rear-wheel numbers. YES, '85 had a more open exhaust that was modified for '86, to compensate the v-boost tubes got larger. Peak power was unchanged, though it occurred at a slightly lower RPM. Still, owners of '85 model bikes will insist they are faster.
23. What is the cylinder arrangement?
From left to right on the crank, 1-2-3-4. Left rear is #1, left front is #2, right rear is #3, right front is #4
24. What about this "dreaded o-ring" problem? How do I know if it's a problem on my bike?
To me, the hype around the o-ring is due to a mistake between correlation and causation. Motors that have failed almost always have popped o-rings, however, that's not necessarily what caused them to fail. There are also thousands of bikes out there that have ridden millions of miles with popped rings and no adverse effects. The Vmax has a high volume oil pump with more than adequate capacity, so a small leak is not enough to cause an excessive loss of pressure. My personal suggestion is that if you're worried about it, get an oil pressure gauge here. This will allow you to keep an eye on it. If the pressure is unsatisfactory, tear into the pan and fix the o-ring. The pressure bypass is at ~58psi, which is what the gauge should read with the engine cold, it will steadily fall as the engine warms. Fully warm with 15-40 oil, I saw 2-3psi at hot idle, which is normal, and a very rough relation is about 5 psi more pressure per 1000rpm. 4500rpm cruise on the highway I usually saw about 25-30psi.
If it's fine, leave it alone, and if a problem arises, you'll know about it. There are fixes available, namely an improved "bumper" and using a Kawasaki oval o-ring that fits tighter. Sean makes a HD oil kit, which not only fixes the problem but improves the pump's capacity by driving it faster.
25. My bike idles poorly/only runs with choke/hesitates/has dead spots/ect
See the Carbs/Tuning forum. Two popular and easy techniques that can cure common running issues are known as the shotgun and peashooter(back out the a/f screws and blast carb cleaner down PAJ #1). That's the one jet visible in the throat of the carbs, follow up with air. If that doesn't help, see the Carbs forum stickies for detailed instructions on how to disassemble, clean, and rebuild them. If you're not up to the job of doing that yourself, you can contact Sean Morley (one2dmax) or Dan (dannymax) about their carb rebuild services.
26. I think my clutch is slipping. What can I do?
First, try changing brand of oils. Synthetic oils tend to promote clutch slippage, try switching to a conventional and see if that helps. However, once the clutch starts to slip, it usually doesn't stop. The stock clutch spring is regarded as too weak, and not really up to the task of the Vmax mill's power. Barnett makes a coil spring conversion, PCW in Schenectady NY makes a stock style heavy duty spring(thicker), or you can just double up with two stock springs (called the DD or double-d mod). While you're in there, sand (or better yet, bead-blast) the steel plates, and just replace the frictions. It's also a good idea to toss the "half disc" farthest back and replace it with a full one (PCW's kit includes everything needed and directions for about $150). All you need is a 5mm hex key and a 10mm wrench and about an hour.
I would suggest sticking with OEM frictions. Stay away from the el cheapo ebay kits. If you opt for the DD mod, try to get two used springs, two new ones will have a very stiff lever pull. The PCW spring is roughly 50% stiffer than stock, and pretty much splits the difference between stock and 2x stock. Still, the DD in traffic can get tiring quickly. A larger diameter clutch cylinder can mitigate this.
27. My bike pops out of 2nd gear on hard acceleration. What do I do?
Sit down, here comes bad news. Pull the engine, take it entirely apart, split the cases, fix the rounded off 2nd gear dogs, and then put it all back together. There's no easy or quick fix. If a bike you're looking at buying has this problem, run(or get it for very cheap). If you have this problem, contact Sean Morley. There are other goodies you might want to do while it's all apart. If it's not popping out good. To keep it that way, always clutch your 1-2 shift.
28. What oil should I put in the final drive, and how often?
Gear oil, and whenever you feel like it. Yamaha says to change it every 24000 km, which is about 15k miles. The spec Yamaha calls for(GL-4) has been long surpassed(now GL-5) so anything out there is a-ok. I usually change it at the start of each season just "to do it". It only holds a few ounces of oil, so the standard 1 quart squeezy bottle will be good for several changes. Yamaha called for 80wt, which to my knowledge isn't really around anymore. 75-90 or 80-90 will be perfectly fine. No need for the 140wt primordial ooze, it's not a posi. Want a suggestion? Lucas 80-90 gear lube. It has Lucas stabilizer already mixed in(so it "climbs" well), and a bottle is around $9 at Tractor Supply. Again, just a suggestion, anything will do.
29. Where are the a/f screws on this bike? I can't find any adjustments.
On stock bikes, they are hidden behind anti-tamper plugs. They're near the bottom of each carb, a bit under the diaphragm covers. You should see a little round plug that looks like it's covering something. To remove them, get a drill and bit about 1/2 the diameter of the plug, and poke a hole in it. The screw is fairly recessed behind the plug, so as long as you drill carefully I wouldn't worry about accidentally hitting the screw. Then either use an angled pick to pry it out, or thread a sheet metal screw into it, grab it with vise grips, and. give it a firm yank. They should pop right out.
30. Do I need "premium" or 91+ octane fuel? Is there any benefit to super high octane, like race fuel?
Short answer: No, and no. Regular 87 is perfectly fine, and is the best fuel for your motor. But to be frank telling this to a lot of people is like telling a 5 year old Santa isn't real, so here's the explanation.
Long answer: Octane is not a magical horsepower juice, as petroleum and additive company marketing would like you to believe. In fact, it's the opposite. Octane ******* combustion, making the fuel less volatile, enabling it to withstand higher compression without pre-ignition. Yamaha does not recommend or suggest premium in any manual. It has been proven that an engine makes the maximum power running the lowest octane possible that prevents preignition. As in, peak power is extracted from the fuel at the edge of it detonating on it's own, at it's state of maximum volatility. Higher octane fuel raises this threshold, and thus the fuel is less volatile when the spark lights it, resulting in a very slightly lower output. We're talking maybe a HP or two, something you'd never feel seat-of-pants. But still....why spend more money for less power? I understand the "nothing but the best" mentality people (myself included) have toward their bikes, but calling a fuel "premium" rather than "hi-test" proved to sell a lot more of it. People wanted to "treat" their cars to "premium" fuel. You don't need to worry about detonation in a stock engine. I've held mine WOT near redline in top gear for several minutes at a time and it never missed a beat on regular 87. If it was ever going to ping, it would then. In the US, there is NO difference in quality, purity, energy content, ect between 87 and 91. It is the exact same base fuel, with one batch getting more octane additive. I've been to fuel pipelines and distribution centers. It's exactly the same.
A popular justification for this is "premium burns cooler", which is perceived as good. This is true, the explosion is slower and less violent, and produces less heat. However, this is not a positive. Stock compression engines that have been run on premium, upon disassembly for whatever reason, nearly always have extensive carbon buildup since the engine is not burning as hot as intended to self-clean itself, to continually burn off these deposits. So they build up on valves, heads, ect.
Just run 87, (or 91 for most other countries in the world). The US and Canada use the RON+MON/2 system, pretty much everyone else uses only the RON, which is typically about 4 points higher for an equivalent fuel.
Race fuel gives your exhaust that whiffy scent motorheads like, but that's it. Any perceptions the bike is faster is just placebo effect from spending $8/gallon.
EDIT: Some fuel stations are now offering ethanol free gas if you select premium. If this is an option, I would choose it, especially for the tank or two prior to seasonal storage. You still don't need the higher octane, but getting rid of the corn squeezins gets you a few percent more energy per gallon, and will slightly improve mileage and power. Plus, it has a much longer shelf life, and the biggie, does not absorb water like ethanol blended fuels do.
I saw a few stations in Canada where regular was 10%, midgrade was 5%, and premium was ethanol-free as well.
31. I have a mystery switch with either 2 or 3 positions, it doesn't seem to do anything.
This could be a fan override switch, in which case flipping it will turn on the cooling fan whenever the key is on. If that doesn't happen, it's most likely a "t-boost" switch. It's a fairly common mod that allows the boost valves to open at 3000rpm instead of the standard 6000. Early boost makes the "butt dyno" say the bike is a little stronger and more responsive, but in reality you're just running too rich and making less power. There's numerous dyno charts out there to prove this. 6000+ is unchanged, but the 3-6000rpm range is several HP softer with the valves open on an otherwise stock setup. These setups basically trick the stock controller into thinking the engine is spinning twice as fast as actual by feeding it the coil pulse signals from 2 coils instead of 1. There are ready-made plug in parts for this, however they're very simple to make with a couple diodes.
32. My bike leaks oil after removing a case cover, despite using a new gasket and cleaning the surfaces.
More than likely you have a warped cover. I removed the left covers to change the stator(first time they'd been broken off since the factory), and had a nagging oil leak that I chased for months afterward. I tried new gaskets, 2 gaskets, sealants, RTV, everything. Nothing worked, at least not for more than a week or two. Finally someone here suggested setting the cover on a flat surface....for me it was a table saw....and the cover would rock. It didn't sit perfectly flat. I used a big disc sander and just pressed the cover up against it. Instantly low spots appeared that weren't touching. Sanded until there were none of these spots, cleared the metal dust out, another new gasket, back together, leak free for over a year now. You must use a gasket on the stator cover, otherwise the starter reduction gear axles will be pinched and bind. For the middle gear and clutch covers it's optional, I'm cheap so I just used Yamabond 4 (aka Threebond 1194) to reseal them. I've had zero problems with leaks.
33. What's this I hear about 1985 models having more power?
Simply put, it's not true. This is a myth that keeps popping up.
The myth stems from the fact the '85 had a louder (as in not meeting highway noise requirements) and less restrictive exhaust. This was revised for '86 up.
To compensate, the v-boost tubes got 2mm larger in diameter. Peak power was unchanged(145hp, or ~112 at the tire), though now it occurred at a slightly lower RPM than it did on the '85 bike.
European models lacked v-boost and thus only had ~90ish hp, to comply with the 100hp restriction.
Japanese models lacked v-boost, and also had a speed limiter(built into the speedometer) that cut ignition to 2 cylinders at 180km/h (112mi/h), per Japanese federal regulation. This is easy to disable though, it's just a switch that's tripped by the speedo needle.
34. What about coolant? What's best?
Regular "green" coolant is fine and what the bike came with from the factory. The service manual specifies to change coolant every 15k miles or two years. Remember that was with 1985 coolant....stuff today is a lot better and carries a much longer service life.
Some people prefer to use the red or pink "Asian" antifreeze since it is specially designed for aluminum engines, or other modern long-life coolants that come in every color of the rainbow. I'm sure these are fine as well if you want to spring for it, but be sure to completely flush all the original green stuff out first, since mixing them can cause adverse effects. Run the engine with straight water after draining the coolant, then drain again before refilling with your choice. Many of these modern automotive factory-fill coolants have service intervals of 100k miles. Or for all intensive purposes, the life of the bike.
There's also several specialty powersports branded coolants out there, such as Engine Ice. They're very expensive and I'm not convinced they work any better than regular stuff. Some people swear by them though. So again, if you want to pay the price of entry, go for it, though be prepared to pay 10-20x as much per-unit than mixing green stuff yourself at home.
My bike never once overheated, or even came close, with a 50/50 mix of distilled water and plain green store brand coolant.
Section 5: Chassis
34. My bike wobbles at (high speed/ on deceleration/hitting bumps/low speed/around corners).
Welcome to the club.
Anyway, there are loads of things that can cause instability. First and easiest is tires. Are they inflated properly? Low pressure causes lots of problems. I believe the spec is 32 front and 36 rear, it's on a sticker underneath the dummy tank cover. Are the tires cupped? (a slightly concave shape on either side of center) That'll cause handling issues. Are the tires old? Any dry rot/cracking? Just replace them. The next most common point is misadjusted head bearings. Look right under the big nut in the center of the handlebars. See the two castellated nuts? Those are used to set the steering/head bearing tension. If the bearings are loose, you'll get the wobbles. If the bearings are tight, you typically get a low-speed weave, like it's difficult to make the bike hold a straight line. Search "vmax head bearing" on youtube and click the first video that comes up for how to properly set the tension. You can also try sliding the fork tubes about 3/4" up in the trees(no more, otherwise the fender will tag the radiator under hard braking), which is free and easy. I like the quicker "flick" it gives, some don't, and it's easy enough to put back to stock.
35. What can I do to improve the bike's handling?
-Ditch the stock tires
-Replace rubber engine mounts with solid(this will stiffen the frame, at the cost of additional vibration)
-Install Progressive fork springs, lower the forks internally an inch
-Add frame/fork braces
-Wider handlebar(Python makes a very nice 30" wide one)
-Braced swingarm
-Slide the forks up the trees 3/4"
36. I don't like the braking power. What are my options?
Install EBC's "HH" pads in your stock calipers. Just those will make a big difference. Still not good enough? People with "new" forks ('93-up) can directly swap several other Yamaha calipers, from the R6/R1/Fazers/FJR. For people with the old forks(85-92), Sean makes adapters to use Hayabusa 6-pot calipers. Getting a sportbike's master cylinder can help as well.
37. My bike cranks slowly when hot, has low voltage, or in general isn't keeping the battery charged. Where do I start?
See this thread by yours truly.
38. I want my bike to sound cool. What are my options?
If you're on a budget, and just desire the look/sound of aftermarket exhaust, there are several slip-on mufflers available. Any are fine, look on youtube for videos of sounds. Supertrapps are a popular slip-on choice, readily available, reasonable cost, and the "tunability" of Trapps with the disc system...can be as loud or quiet as you want. Avoid Cobras, they really kill power.
Slip-ons won't add any power, but you will lose probably 10-15lbs if not more of weight, the stock muffler is a brick. For full systems, expect to spend around a grand. Kerker, Holeshot, Marks, and Jardine are some of the more common systems. Again...personal taste should dictate. Sounds range from mild street baffles to wild open race cans. They are available in 4-1 and 4-2 styles.
39. Do I need to re-jet after changing the exhaust?
For slip-ons with stock headers, it's not essential, though Sean has recommended 147.5 mains for slip-on exhausts, slightly leaner than stock to compensate for reduced back pressure. After this change I noticed upper rev range throttle response seemed to be a bit crisper and snappier. But it also ran perfectly fine before with stock jets. Your call.
For full systems, yes. Running a full system with stock jetting, there may be HP gains, but not to full potential. The best option to mate a full system with is Sean's Muscle jet kit, which modifies the stock airbox and includes jets needed. It also outperforms the DJ Stage 7(equal top end, but with better midrange), at a lower cost.
Hopefully that should take care of your initial questions. If you really want to earn that gold star, look in all the forums at the sticky topics highlighted at the top of the thread listings. They contain noteworthy posts, information, et cetera and are worth your time to at least browse. If you have new info to add to this FAQ please send me a PM and I'll add it.
Edits:
12/22- Fixed tire size error, fixed a couple typos, added tire size info, cleaned up formatting, changed Q's color, added jetting info
1/1- Fixed cylinder # error
1/7- added a couple more oil q's, clarified a few points
3/22- added another q, clarified a couple points
3/31- fixed a few typos, clarified few details
4/3- added filter info
4/10- revised filter info
4/28- added t-boost info
5-29- added another q
6/2- added tip about Hindle headers
7/28- added info about power in '85
6/2/13- Revised oil info, tire info
Special thanks to:
ninjaneer- for suggesting several clarifications and additions
naughtyg- pointing out some typos and suggestions
Thevmaxrider- suggesting the stainless oil filter
midmoraider- tip about oil filter/Hindle headers
Here at VMF, we love new members, those of you brave enough to welcome a V-max into your garage, and the pet mod-monkeys that tend to nest somewhere between the rear head and fuel tank. We realize new owners are going to have a lot of questions, since the Vmax does have some unique/unusual features, as well as several quirks that may puzzle the new owner. While everyone here wants to help, several questions come up again and again with frankly annoying frequency. Which isn't your fault in the slightest, but it's time we compile all these "noob FAQs" into a single document. It'll hopefully answer many if not all of your new-to-me bike questions in one fell swoop. Hopefully this will be around for millenia worth of vmax owners, if a mod stickies it somehwere.
I'll preface this by saying/admitting that I am cheap. I don't mind spending money when it's needed, but I hate over-paying when it's simply not needed or just overkill. I don't believe in "whatever costs the most is the best" or "if some is good more is better". The couple suggestions given in this article are for products that I feel are a good value and that in my experience perform just as well if not better than more expensive/"premium" brands. Feel free to ignore them.
Section 1: Oil
1. I just got my bike, and want to change the oil in it. Which oil is best to use?
This is probably the single most frequently asked question, so here's the short answer:
Any oil is fine, so long as it doesn't say "high mileage" or "energy conserving". These contain friction modifiers that can cause clutch slippage.
2. Should I use conventional (dino oil), or synthetic? Do I need motorcycle-specific oils?
This is another "area of personal preference". Yamaha did not specify or require any sort of synthetic lubricants and almost universally oils on store shelves now are far better than they were in 1985. The oil spec Yamaha called for(a normal automotive spec) has been long superseded. It is entirely up to you, and in reality, will make very little difference. Your riding style and maintenance habits have far more effect on engine life than does whether or not you sprung for that expensive synthetic or not.
That said, I personally feel that top shelf synthetics are not ideal for the Vmax. Full synthetics have been associated with clutch slippage(especially with the marginal stock clutch spring), and I can attest they can cause starter clutch issues(mine would often fail to "catch" in cool weather with full syn, after switching to rotella, it's never missed again). It's also not uncommon for an engine to be oil-tight, then develop a leak shortly after the oil is changed to synthetic especially on older motors, or ones that have been resealed with a liquid gasket rather than a real one. While you can argue the "correct" solution is to replace the gasket, in many cases you would rather just avoid the problem in the first place.
Do you need motorcycle specific oils? No. People have well over 100k on their original engines using nothing but plain old car oil. Will it hurt? No. So once again, your taste and budget should dictate.
So, my personal suggestion would be to stick with a conventional oil. Take it with a grain of sand.
3. Come on, any suggestions? I'm critically indecisive and can't pick an oil.
Many members here use Shell Rotella-T conventional 15-40. It's a heavy duty (aka diesel) oil, which has more ZDDP(an extreme pressure zinc lubricant). I noticed it smoothed out shifting and made neutral easier to find over Mobil 1 full synthetic. There are NO problems with using "diesel" oil in a gas engine. It comes in 1 gallon jugs, which are $13 at wal-mart. Your bike takes around 3.5 quarts, you'll have a little left over for your lawnmower or something. It's proven, cheap, and very easy to find, virtually any place that sells motor oil has it.
4. What weight should I use?
Yamaha specified 10w-40, same as pretty much every other wet clutch engine out there. To really understand this (and it's a lot more complex than most people think), I'd suggest you read through this.
It's several pages, but has a lot of good info and explains the subject in depth. Still, here's the sparknotes version.
The first number reflects the oil's viscosity, or "weight", with a cold engine, and the second number is for the oil at operating temperature (lets say ~200* F). It's widely stated that 90% of engine wear occurs at startup, so it only makes sense that we focus our oil choice on preventing this startup wear. A 0W-30 oil gives the same hot engine protection as a 10-30, but will reduce wear at startup by flowing quicker and easier. There's also some misconceptions about oil pressure, with a notion that more is better. While it's certainly bad if you have zero across the board, keep in mind pressure is defined as a "resistance to flow". This is why pressure is very high on a cold engine, the oil is very resistant to flowing, and it falls off as it warms. Oil flow is much more important than pressure, more flow means more lubrication and more cooling. Zero indicated pressure on a hot idle does NOT mean that no oil is flowing, but rather that it is flowing with almost no resistance, and shouldn't be any cause for concern. Even in the owner's manual of my Z is says it's "no cause for concern" if the oil pressure light comes on at idle, so long as it goes off again once RPMs are raised. But the old conventional wisdom says that very thin oil does not "cushion" between parts as well and will not protect as well. Simply put, this isn't true. Thicker "hot" oils can help to quiet a tired, loose engine, or an older mill with greater tolerances. For modern engines(and you can call the Vmax modern), this thicker oil needs more force to squeeze it through the tight tolerances and smaller galleys, which raises pressure and saps energy from the engine.
But what about hot climates? "I live in Florida and frequently have to ride in stop-and-go traffic where the engine gets very hot." Again, your coolant gets hot due to the lack of airflow, hindering the radiator's ability to get rid of the heat. The oil will get a little warmer, but idling in traffic has the engine under little to no load at low RPMs, and a thicker oil would not help it cool better (to the contrary, it flows and circulates less, transferring less heat from the parts).
So, what to use? Yamaha says 10-40, but you're suggesting that thinner is better.
Here's where it's up to you. People like to tout they've "never had any problems" with Brand X oil of their choice, therefore it is a good oil. Frankly, engine failures due to a poor quality oil are virtually unheard of these days, so that's not a very good argument. Specifically to motorcycles, some brands of oil do have noticeable effects on shift action, clutch wear and clutch drag. Neutral being difficult to find is a sign the clutch is dragging more, from a less slippery oil (or clutch problems, but we'll assume it's in good order). I have used 10-40, 15-40, and recently 0-30 in various bikes I've owned. While I sold my Vmax last summer and can't give a direct comparison on that, I did change on my Z, from the 15-40 Rotella conventional to the 5w-40 Rotella T6 synthetic Cold cranking is faster and easier, and the motor is quieter in the few seconds after startup. Shift action is lighter and easier as well, which does back up what "Bob the Oil Guy" claims.
So the conclusion is that really any oil is suitable, and short of pouring 50w in for dead winters of Alaska, will not cause problems. Long term wear can be minimized by using a thinner multi-grade oil of either conventional or synthetic. Synthetics have better flow characteristics than a conventional of an equal grade, and have longer service intervals (many new bikes specify 7500 or more miles between changes). Of course, synthetics cost 2-3x more.
You're armed with the info, now make your own choice.
5. How often should I change it?
How ever often helps you sleep at night. To me, any more often than every 3000mi is just wasting perfectly good oil, assuming normal street riding, but excessive oil changing never hurt anything, so if you want to, go for it. My trick for the Vmax (and this is just a personal observation), is to change it when neutral starts getting hard to find, meaning the clutch is dragging more than it used to. I usually did every 5k miles, and scheduled them on the 5's....so 20,000 miles, 25k, 30k, ect, keeps it easy to remember. If you use your bike on the strip or track regularly, more frequent changes are advisable.
6. What about filters?
For 85-95 bikes, you take a cartridge style filter, and don't have a ton of choices. Fram CH6002, OEM Yamaha, or a generic aftermarket.
For 96-07 bikes, you take a spin-on style, and have loads of choices. Fram PH6017, Purolator ML16817, NAPA Gold 1358 are all MC-specific filters. Some members reference a Bosch 3323 automotive filter as well. Note that the 3323 is too long for use with Hindle headers, though the shorter 3330 does fit.
A "top shelf" choice is a K&N filter. Part # KN303. They're commonly found in black, but some stores carry the chrome versions as well. Otherwise you can get them on ebay if you want the shiny.
There are also stainless mesh reusable filters out there, but they're around $100. PC Racing's "FLO" filter is fairly common.
Stick a couple small puck magnets to the outside of the filter, if you cut it open when you change you'll see a big glob of nasty collected on top of where the magnet was. You can get a pack of these at any hardware store for like a dollar.
It can be noted that Bosch, Mobil1, and Supertech (wal-mart) are all made by Champion Labs, the only difference is the filter media. NAPA Gold and Carquest Premium are identical to (and made by) WIX.
Fram filters have a lot of evidence against them, and if you poke around you can find lots of horror stories related to their failure. They're built with cost, not quality in mind. While I'd consider some of the tales out there definitely to be exceptions rather than the norm, higher quality filters are only a dollar or two more expensive, so why compromise?
7. I want to read 30+ pages of oil-related discussion. Can you help?
Sure! Click here.
Section 2: Tires
8. Which tires are best for the Vmax?
From popular vote, there seems to be two favorites. Your budget and riding style should dictate:
Metzeler Marathon ME880.
+Good tread life...8-10k if you don't burn out at every stoplight.
+Excellent handling. Far improved over stock Dunlops
+High quality...balance easily
-Expensive
-Not as sticky as Shinkos
*Note: The ME880 now has the ME888 Marathon Ultra version as well. The 888's are available in the 170 rear for the vmax, but not in a size that fits the front.
Shinko Tourmaster T230
+Cheap. Cost about 60% of what the Metzelers do.
+Very sticky. Superb traction.
-Wear very quickly...often done in only a couple thousand miles
-Taiwanese quality, or lack thereof. Often need loads of weight to balance, and have been known to wear poorly/unevenly.
9. Can I put bigger tires on my Vmax?
Yes. Both the above tires are made in the Vmax stock size (bias ply)
110/90-18 front
150/90-15 rear
as well as the "bigger" options
120/80-18 front (120/90-18 for the Shinko)
170/80-15 rear
Larger than that requires aftermarket rims. The 170 rear tire swap is very popular, and the 170 rear is typically cheaper as well since the 150 is considered a "specialty" size and the 170 is more widely used. Switching to the 120 front will throw off your speedometer, and is not as widely done. It is possible to put a radial tire on the front rim, but nobody makes 15" radial tires, and mixing bias and radial tires is not recommended.
10. What do the tire size #'s mean?
Width/aspect ratio- rim diameter
For example, 110/90-18 means the tire is 110mm wide, is 90% as tall(profile) as it is wide, and is for an 18" rim.
Section 3: Controls/cockpit (giggle now.....)
11. Whats that "whirr-WHIRR"/ clicking noise I hear every time I turn the key on(or flip the kill switch to run)?
That is your v-boost servo self-testing itself. It is perfectly normal. It opens, then closes the valves to let you know it's working. It is controlled by the engine's computer, and opens them around 6000RPM. It gives the same effect as a 4-barrel carb opening the second two at full throttle, however they are controlled by RPM, not throttle position. This is the "whirr-whirr". The "clicking" is the fuel pump topping up the carb bowls. It should click rapidly, and then slow to a stop as the bowls fill. If it constantly clicks(runs) rapidly, or does not slow/stop after a couple key cycles, you could have a bad fuel pump(or a fuel line leak, or leaky needle/seat).
12. What's the deal with the fuel light and reserve switch? How's that work?
The Vmax has a sensor in the tank, set so a small filament is placed corresponding to the level of about .9 gallons left. At all times, current is passed through the filament, but the gasoline acts as a heat sink and prevents it from heating up. When the filament it cool, it has a very high resistance. When the fuel level drops below the filament, it begins to heat up. As it warms, it's resistance drops and power is slowly allowed through...why the fuel light slowly fades on, and never gets very bright. This also trips a relay that shuts off power to the fuel pump...this is Yamaha's way of simulating an actual reserve valve, and to ensure the bike "gets your attention" should you miss the fuel light(the bike will start to spit and sputter a minute or two after you see the light). Flipping the switch to "res" simply restores power to the fuel pump and allows the rest of the tank to be used. It should be noted to always leave this in the "on" position except when needed. Otherwise, you will get no noticeable warning(other than the dim fuel light, which is very easy to miss in bright daylight) until you are completely out of fuel.
13. I've noticed my oil light comes on or flickers under acceleration.
Perfectly normal, and nothing to worry about. Yamaha is stuck on putting oil level sensors on it's bikes, instead of a pressure sensor like everything else has. They also put it in the front of the pan(the oil pump pickup is thankfully in the rear). Under acceleration, the oil sloshes to the back, the sensor is momentarily dry, and the light comes on. As long as the oil is to the upper hashmark in the sight glass, you're fine.
14. Does the Vmax have a rev limiter at the redline?
No, it doesn't. Be careful. This motor does not tolerate over-revving well. An aftermarket Dyna ignition can add this feature, many people install a shift light on the speedometer to help prevent accidental over-revving.
15. My temp gauge hovers near the red zone when in traffic....is this a problem?
Close to the red zone is normal...the fan kicks on at 220*, which corresponds to slightly shy of the red line on the gauge. So long as it doesn't go into the red, you should be OK. It's fairly popular to add a manual fan override switch, to turn the fan on earlier(a switch that simply shorts together the two wires going to the fan switch), or swap out the stock fan thermo switch with one from a '88 Nissan Sentra, which trips the fan at like 190* or something. Your call.
16.160mph speedometer....how fast does the Vmax actually go?
With absolutely ideal conditions, about 150 mph, which corresponds to redline in fifth gear. Actually reaching this speed requires a very smooth, long road and a pair that clank. This bike is not particularly known for it's high speed stability and is fairly prone to headshake/wobbles. If you decide to venture above posted speed limits (on closed circuits only, obviously) do so with caution. Cover the rear brake and use your lower body to support your torso- don't death grip the handlebars as this can cause instability. If you do feel shudder/shakes coming on, gradually roll off the throttle and smoothly apply the rear brake only to scrub off speed until it stabilizes. A panic stab at the front brake or other abrupt maneuvers can cause a full on tank slapper. You might notice pushing the handlebars away from you tends to make wiggles and shakes go away. DO NOT do this. I repeat, DO NOT EVER do this. Without getting into a long explanation, you temporarily mask symptoms of an imbalance, while that imbalance grows with more speed, that can suddenly and violently manifest. Meaning: instant tank slapper. Instant crash. Handlebar being wrenched so hard it breaks your wrist. I can't stress this enough- DON'T.
Personally, with a Venture final drive, stock power output, and my 190lb *** onboard, I would see 140-142 or so on flat ground. I nudged 145 with a bit of a downhill. Your results may vary.
17. My speedometer needle jiggles or "bounces", what's wrong?
Most likely a sticky cable. Remove the speedometer cable at the wheel and blast wd40 or PB Blaster(which seems to penetrate faster) both into the drive, and the cable. Remove it at the speedometer(requires a bit of digging, but not bad), and do the same. Spray lube, let it soak down a bit, spray again. Do this several times, then put it back on and go for a drive. More than likely the needle will be smooth.
18. What is the expected range/ MPG of this bike?
If your bike is running well, and you don't use v-boost too too often, you should see at least 100 miles to the fuel light. A general average from members here is usually 110-120 miles to the light. From the light, you've got a bit less than a gallon left. I wouldn't push it any farther than 20 miles on reserve. Vmax is a heavy bike, not fun to push.
For MPG, that works out to high 30's to low 40's. Mine usually returned right around 38-39mpg on average.
19. Is there anything I can do to improve my mileage?
Assuming your motor is running well and carbs in good shape, you can swap in a Venture final drive. This will lower your RPMs across the board by 10% and net you an extra couple MPGs, at the expense of some acceleration. Sean Morley can give you an overdrive 5th gear as well, though it involves pulling the motor and splitting the cases, so probably best to do if you've got it apart for some other reason also.
20. Do I need the seat bolts?
No. Remove all 4 and toss them. The seat cannot come off when the fuel door is clipped down. This just saves time to get at the battery, fuses, ect.
21. How do I put gas in the damn thing?
Reach under the seat on either side, just in front of the top of the rear shocks. There are two little black levers. Press both forward at the same time and the seat's hump will flip forward to reveal the gas cap.
Section 4: Motor/Carbs
22. How powerful is the Vmax?
All years 85-07, are 145hp (at the crank). Rear-wheel HP(what actually matters) is around 115 for a stock bike in good tune. A full exhaust system(not just slip ons) and good jetting can add 10+hp to your rear-wheel numbers. YES, '85 had a more open exhaust that was modified for '86, to compensate the v-boost tubes got larger. Peak power was unchanged, though it occurred at a slightly lower RPM. Still, owners of '85 model bikes will insist they are faster.
23. What is the cylinder arrangement?
From left to right on the crank, 1-2-3-4. Left rear is #1, left front is #2, right rear is #3, right front is #4
24. What about this "dreaded o-ring" problem? How do I know if it's a problem on my bike?
To me, the hype around the o-ring is due to a mistake between correlation and causation. Motors that have failed almost always have popped o-rings, however, that's not necessarily what caused them to fail. There are also thousands of bikes out there that have ridden millions of miles with popped rings and no adverse effects. The Vmax has a high volume oil pump with more than adequate capacity, so a small leak is not enough to cause an excessive loss of pressure. My personal suggestion is that if you're worried about it, get an oil pressure gauge here. This will allow you to keep an eye on it. If the pressure is unsatisfactory, tear into the pan and fix the o-ring. The pressure bypass is at ~58psi, which is what the gauge should read with the engine cold, it will steadily fall as the engine warms. Fully warm with 15-40 oil, I saw 2-3psi at hot idle, which is normal, and a very rough relation is about 5 psi more pressure per 1000rpm. 4500rpm cruise on the highway I usually saw about 25-30psi.
If it's fine, leave it alone, and if a problem arises, you'll know about it. There are fixes available, namely an improved "bumper" and using a Kawasaki oval o-ring that fits tighter. Sean makes a HD oil kit, which not only fixes the problem but improves the pump's capacity by driving it faster.
25. My bike idles poorly/only runs with choke/hesitates/has dead spots/ect
See the Carbs/Tuning forum. Two popular and easy techniques that can cure common running issues are known as the shotgun and peashooter(back out the a/f screws and blast carb cleaner down PAJ #1). That's the one jet visible in the throat of the carbs, follow up with air. If that doesn't help, see the Carbs forum stickies for detailed instructions on how to disassemble, clean, and rebuild them. If you're not up to the job of doing that yourself, you can contact Sean Morley (one2dmax) or Dan (dannymax) about their carb rebuild services.
26. I think my clutch is slipping. What can I do?
First, try changing brand of oils. Synthetic oils tend to promote clutch slippage, try switching to a conventional and see if that helps. However, once the clutch starts to slip, it usually doesn't stop. The stock clutch spring is regarded as too weak, and not really up to the task of the Vmax mill's power. Barnett makes a coil spring conversion, PCW in Schenectady NY makes a stock style heavy duty spring(thicker), or you can just double up with two stock springs (called the DD or double-d mod). While you're in there, sand (or better yet, bead-blast) the steel plates, and just replace the frictions. It's also a good idea to toss the "half disc" farthest back and replace it with a full one (PCW's kit includes everything needed and directions for about $150). All you need is a 5mm hex key and a 10mm wrench and about an hour.
I would suggest sticking with OEM frictions. Stay away from the el cheapo ebay kits. If you opt for the DD mod, try to get two used springs, two new ones will have a very stiff lever pull. The PCW spring is roughly 50% stiffer than stock, and pretty much splits the difference between stock and 2x stock. Still, the DD in traffic can get tiring quickly. A larger diameter clutch cylinder can mitigate this.
27. My bike pops out of 2nd gear on hard acceleration. What do I do?
Sit down, here comes bad news. Pull the engine, take it entirely apart, split the cases, fix the rounded off 2nd gear dogs, and then put it all back together. There's no easy or quick fix. If a bike you're looking at buying has this problem, run(or get it for very cheap). If you have this problem, contact Sean Morley. There are other goodies you might want to do while it's all apart. If it's not popping out good. To keep it that way, always clutch your 1-2 shift.
28. What oil should I put in the final drive, and how often?
Gear oil, and whenever you feel like it. Yamaha says to change it every 24000 km, which is about 15k miles. The spec Yamaha calls for(GL-4) has been long surpassed(now GL-5) so anything out there is a-ok. I usually change it at the start of each season just "to do it". It only holds a few ounces of oil, so the standard 1 quart squeezy bottle will be good for several changes. Yamaha called for 80wt, which to my knowledge isn't really around anymore. 75-90 or 80-90 will be perfectly fine. No need for the 140wt primordial ooze, it's not a posi. Want a suggestion? Lucas 80-90 gear lube. It has Lucas stabilizer already mixed in(so it "climbs" well), and a bottle is around $9 at Tractor Supply. Again, just a suggestion, anything will do.
29. Where are the a/f screws on this bike? I can't find any adjustments.
On stock bikes, they are hidden behind anti-tamper plugs. They're near the bottom of each carb, a bit under the diaphragm covers. You should see a little round plug that looks like it's covering something. To remove them, get a drill and bit about 1/2 the diameter of the plug, and poke a hole in it. The screw is fairly recessed behind the plug, so as long as you drill carefully I wouldn't worry about accidentally hitting the screw. Then either use an angled pick to pry it out, or thread a sheet metal screw into it, grab it with vise grips, and. give it a firm yank. They should pop right out.
30. Do I need "premium" or 91+ octane fuel? Is there any benefit to super high octane, like race fuel?
Short answer: No, and no. Regular 87 is perfectly fine, and is the best fuel for your motor. But to be frank telling this to a lot of people is like telling a 5 year old Santa isn't real, so here's the explanation.
Long answer: Octane is not a magical horsepower juice, as petroleum and additive company marketing would like you to believe. In fact, it's the opposite. Octane ******* combustion, making the fuel less volatile, enabling it to withstand higher compression without pre-ignition. Yamaha does not recommend or suggest premium in any manual. It has been proven that an engine makes the maximum power running the lowest octane possible that prevents preignition. As in, peak power is extracted from the fuel at the edge of it detonating on it's own, at it's state of maximum volatility. Higher octane fuel raises this threshold, and thus the fuel is less volatile when the spark lights it, resulting in a very slightly lower output. We're talking maybe a HP or two, something you'd never feel seat-of-pants. But still....why spend more money for less power? I understand the "nothing but the best" mentality people (myself included) have toward their bikes, but calling a fuel "premium" rather than "hi-test" proved to sell a lot more of it. People wanted to "treat" their cars to "premium" fuel. You don't need to worry about detonation in a stock engine. I've held mine WOT near redline in top gear for several minutes at a time and it never missed a beat on regular 87. If it was ever going to ping, it would then. In the US, there is NO difference in quality, purity, energy content, ect between 87 and 91. It is the exact same base fuel, with one batch getting more octane additive. I've been to fuel pipelines and distribution centers. It's exactly the same.
A popular justification for this is "premium burns cooler", which is perceived as good. This is true, the explosion is slower and less violent, and produces less heat. However, this is not a positive. Stock compression engines that have been run on premium, upon disassembly for whatever reason, nearly always have extensive carbon buildup since the engine is not burning as hot as intended to self-clean itself, to continually burn off these deposits. So they build up on valves, heads, ect.
Just run 87, (or 91 for most other countries in the world). The US and Canada use the RON+MON/2 system, pretty much everyone else uses only the RON, which is typically about 4 points higher for an equivalent fuel.
Race fuel gives your exhaust that whiffy scent motorheads like, but that's it. Any perceptions the bike is faster is just placebo effect from spending $8/gallon.
EDIT: Some fuel stations are now offering ethanol free gas if you select premium. If this is an option, I would choose it, especially for the tank or two prior to seasonal storage. You still don't need the higher octane, but getting rid of the corn squeezins gets you a few percent more energy per gallon, and will slightly improve mileage and power. Plus, it has a much longer shelf life, and the biggie, does not absorb water like ethanol blended fuels do.
I saw a few stations in Canada where regular was 10%, midgrade was 5%, and premium was ethanol-free as well.
31. I have a mystery switch with either 2 or 3 positions, it doesn't seem to do anything.
This could be a fan override switch, in which case flipping it will turn on the cooling fan whenever the key is on. If that doesn't happen, it's most likely a "t-boost" switch. It's a fairly common mod that allows the boost valves to open at 3000rpm instead of the standard 6000. Early boost makes the "butt dyno" say the bike is a little stronger and more responsive, but in reality you're just running too rich and making less power. There's numerous dyno charts out there to prove this. 6000+ is unchanged, but the 3-6000rpm range is several HP softer with the valves open on an otherwise stock setup. These setups basically trick the stock controller into thinking the engine is spinning twice as fast as actual by feeding it the coil pulse signals from 2 coils instead of 1. There are ready-made plug in parts for this, however they're very simple to make with a couple diodes.
32. My bike leaks oil after removing a case cover, despite using a new gasket and cleaning the surfaces.
More than likely you have a warped cover. I removed the left covers to change the stator(first time they'd been broken off since the factory), and had a nagging oil leak that I chased for months afterward. I tried new gaskets, 2 gaskets, sealants, RTV, everything. Nothing worked, at least not for more than a week or two. Finally someone here suggested setting the cover on a flat surface....for me it was a table saw....and the cover would rock. It didn't sit perfectly flat. I used a big disc sander and just pressed the cover up against it. Instantly low spots appeared that weren't touching. Sanded until there were none of these spots, cleared the metal dust out, another new gasket, back together, leak free for over a year now. You must use a gasket on the stator cover, otherwise the starter reduction gear axles will be pinched and bind. For the middle gear and clutch covers it's optional, I'm cheap so I just used Yamabond 4 (aka Threebond 1194) to reseal them. I've had zero problems with leaks.
33. What's this I hear about 1985 models having more power?
Simply put, it's not true. This is a myth that keeps popping up.
The myth stems from the fact the '85 had a louder (as in not meeting highway noise requirements) and less restrictive exhaust. This was revised for '86 up.
To compensate, the v-boost tubes got 2mm larger in diameter. Peak power was unchanged(145hp, or ~112 at the tire), though now it occurred at a slightly lower RPM than it did on the '85 bike.
European models lacked v-boost and thus only had ~90ish hp, to comply with the 100hp restriction.
Japanese models lacked v-boost, and also had a speed limiter(built into the speedometer) that cut ignition to 2 cylinders at 180km/h (112mi/h), per Japanese federal regulation. This is easy to disable though, it's just a switch that's tripped by the speedo needle.
34. What about coolant? What's best?
Regular "green" coolant is fine and what the bike came with from the factory. The service manual specifies to change coolant every 15k miles or two years. Remember that was with 1985 coolant....stuff today is a lot better and carries a much longer service life.
Some people prefer to use the red or pink "Asian" antifreeze since it is specially designed for aluminum engines, or other modern long-life coolants that come in every color of the rainbow. I'm sure these are fine as well if you want to spring for it, but be sure to completely flush all the original green stuff out first, since mixing them can cause adverse effects. Run the engine with straight water after draining the coolant, then drain again before refilling with your choice. Many of these modern automotive factory-fill coolants have service intervals of 100k miles. Or for all intensive purposes, the life of the bike.
There's also several specialty powersports branded coolants out there, such as Engine Ice. They're very expensive and I'm not convinced they work any better than regular stuff. Some people swear by them though. So again, if you want to pay the price of entry, go for it, though be prepared to pay 10-20x as much per-unit than mixing green stuff yourself at home.
My bike never once overheated, or even came close, with a 50/50 mix of distilled water and plain green store brand coolant.
Section 5: Chassis
34. My bike wobbles at (high speed/ on deceleration/hitting bumps/low speed/around corners).
Welcome to the club.
Anyway, there are loads of things that can cause instability. First and easiest is tires. Are they inflated properly? Low pressure causes lots of problems. I believe the spec is 32 front and 36 rear, it's on a sticker underneath the dummy tank cover. Are the tires cupped? (a slightly concave shape on either side of center) That'll cause handling issues. Are the tires old? Any dry rot/cracking? Just replace them. The next most common point is misadjusted head bearings. Look right under the big nut in the center of the handlebars. See the two castellated nuts? Those are used to set the steering/head bearing tension. If the bearings are loose, you'll get the wobbles. If the bearings are tight, you typically get a low-speed weave, like it's difficult to make the bike hold a straight line. Search "vmax head bearing" on youtube and click the first video that comes up for how to properly set the tension. You can also try sliding the fork tubes about 3/4" up in the trees(no more, otherwise the fender will tag the radiator under hard braking), which is free and easy. I like the quicker "flick" it gives, some don't, and it's easy enough to put back to stock.
35. What can I do to improve the bike's handling?
-Ditch the stock tires
-Replace rubber engine mounts with solid(this will stiffen the frame, at the cost of additional vibration)
-Install Progressive fork springs, lower the forks internally an inch
-Add frame/fork braces
-Wider handlebar(Python makes a very nice 30" wide one)
-Braced swingarm
-Slide the forks up the trees 3/4"
36. I don't like the braking power. What are my options?
Install EBC's "HH" pads in your stock calipers. Just those will make a big difference. Still not good enough? People with "new" forks ('93-up) can directly swap several other Yamaha calipers, from the R6/R1/Fazers/FJR. For people with the old forks(85-92), Sean makes adapters to use Hayabusa 6-pot calipers. Getting a sportbike's master cylinder can help as well.
37. My bike cranks slowly when hot, has low voltage, or in general isn't keeping the battery charged. Where do I start?
See this thread by yours truly.
38. I want my bike to sound cool. What are my options?
If you're on a budget, and just desire the look/sound of aftermarket exhaust, there are several slip-on mufflers available. Any are fine, look on youtube for videos of sounds. Supertrapps are a popular slip-on choice, readily available, reasonable cost, and the "tunability" of Trapps with the disc system...can be as loud or quiet as you want. Avoid Cobras, they really kill power.
Slip-ons won't add any power, but you will lose probably 10-15lbs if not more of weight, the stock muffler is a brick. For full systems, expect to spend around a grand. Kerker, Holeshot, Marks, and Jardine are some of the more common systems. Again...personal taste should dictate. Sounds range from mild street baffles to wild open race cans. They are available in 4-1 and 4-2 styles.
39. Do I need to re-jet after changing the exhaust?
For slip-ons with stock headers, it's not essential, though Sean has recommended 147.5 mains for slip-on exhausts, slightly leaner than stock to compensate for reduced back pressure. After this change I noticed upper rev range throttle response seemed to be a bit crisper and snappier. But it also ran perfectly fine before with stock jets. Your call.
For full systems, yes. Running a full system with stock jetting, there may be HP gains, but not to full potential. The best option to mate a full system with is Sean's Muscle jet kit, which modifies the stock airbox and includes jets needed. It also outperforms the DJ Stage 7(equal top end, but with better midrange), at a lower cost.
Hopefully that should take care of your initial questions. If you really want to earn that gold star, look in all the forums at the sticky topics highlighted at the top of the thread listings. They contain noteworthy posts, information, et cetera and are worth your time to at least browse. If you have new info to add to this FAQ please send me a PM and I'll add it.
Edits:
12/22- Fixed tire size error, fixed a couple typos, added tire size info, cleaned up formatting, changed Q's color, added jetting info
1/1- Fixed cylinder # error
1/7- added a couple more oil q's, clarified a few points
3/22- added another q, clarified a couple points
3/31- fixed a few typos, clarified few details
4/3- added filter info
4/10- revised filter info
4/28- added t-boost info
5-29- added another q
6/2- added tip about Hindle headers
7/28- added info about power in '85
6/2/13- Revised oil info, tire info
Special thanks to:
ninjaneer- for suggesting several clarifications and additions
naughtyg- pointing out some typos and suggestions
Thevmaxrider- suggesting the stainless oil filter
midmoraider- tip about oil filter/Hindle headers
Last edited:
![Bovemanx Motorcycle Phone Mount Holder, [150mph Wind Anti-Shake][7.2inch Big Phone Friendly] Bike Phone Holder, Motorcycle Handlebar Cell Phone Clamp, Compatible with iPhone 16 Pro Max Smartphones](https://m.media-amazon.com/images/I/51F+1sontPL._SL500_.jpg)
