My Vmax performing like a 500cc

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TCI-Transistor Controlled Ignition
CDI- Capacitor Discharge Ignition
ECU- Electronic Control Unit
 
TCI-Transistor Controlled Ignition
CDI- Capacitor Discharge Ignition
ECU- Electronic Control Unit

Cool thanks Blaxmax!

**now can someone translate that to me in English?**

I'm scared about what happens when electrical issues will/may go bad with my bike, it's so sophisticated, are the wires going to just go bad, bad connections, etc.? I mean, d*mn, they're 31 yrs old!
 
Yes they are going to go bad-I am fortunate as one of mine is an '85 with very low mileage-13,000 and garaged the whole time. I have only had to replace the battery, r/r,coils(upgraded to cops) headlight, main fuse, it had no blinkers when I bought it- also had no heat shields anywhere and I bought all of those and more-I bought 2 of the rear that hold the plugs and cut and use it on front to hold cops.Also changed my vboost to manual cable.
 
Cool thanks Blaxmax!

**now can someone translate that to me in English?**

I'm scared about what happens when electrical issues will/may go bad with my bike, it's so sophisticated, are the wires going to just go bad, bad connections, etc.? I mean, d*mn, they're 31 yrs old!

The ECU, electronic control unit is the brain of the vehicle, it tells everything else when to fire, etc.

Wires dont just go bad....now corrosion "green coloring" or sometimes "white" can set into wire around the connectors, and will not allow electricity to go thru. The corrosion can be cleaned off.

Anything wrong with the bike can be fixed on this forum.....but one thing to come to grips with, you will probably have to do the work yourself. Dealerships are not what they should be, but....like I said, this forum can walk you thru any issue that you have.

EDIT** Do you have a manual for your bike?
 
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The ECU, electronic control unit is the brain of the vehicle, it tells everything else when to fire, etc.

Wires dont just go bad....now corrosion "green coloring" or sometimes "white" can set into wire around the connectors, and will not allow electricity to go thru. The corrosion can be cleaned off.

Anything wrong with the bike can be fixed on this forum.....but one thing to come to grips with, you will probably have to do the work yourself. Dealerships are not what they should be, but....like I said, this forum can walk you thru any issue that you have.

EDIT** Do you have a manual for your bike?

I think I got the manual thing covered
 

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Alright, started the carb rebuild project yesterday. Took the rack out, wasn't as intimidating as it was 2 yrs ago when I did it for the first time. Didn't even get disassembling it before my buddy swung by, and well the cocktails were poured and darts were placed, conversations were had. I guess I'll have to start it up tonight.

One thing I did notice though, when I emptied the carb bowls, Carb #4 did not have anything come out...

In addition, it will be a few days before I get it all disassembled and cleaned, but I would like to start thinking about the jets.....

*what is a jet kit and what's in it? Is it just different sized pilot jet, etc...?

Years back my, back then mechanic Vmax guru guy put in Stage 1... I didn't know any better at the time what that really meant or anything. On this rebuild, I am willing to consider better options for performance, if available. Recommendations welcome...
 
First of all, the only usable part in a stage 1 kit is the needles. So what all did he "put" in there? If he did the complete stage 1 kit, you halfway to a stage 7 kit....or Seans Muscle jet kit which is a hybrid kit.

Do you have a full aftermarket exhaust? It doesnt matter what kit, but you dont really get benefits without a full aftermarket exhaust.

Regardless of what kit you use, you will need air correctors. Stage 7 springs (If you dont have them, they are part of the stage 1 kit) You will need to drill the slides (if they werent drilled with the stage 1 kit, and they are part of the usual stage 1 kit), stage 7 needles, either aftermarket pod filters and catch can, or Seans muscle jet filter lid (and you use the stock airbox), and the barbed oil filler lid (that will T into the catch can, or the stock air box for Seans kit), and jets, probably 147.5's thru 152.5s. Some people will run a bigger pilot jet (40, instead of the stock 37.5)

Me personally, I like Seans kit, it seems to have better midrange than the stage 7 kit.

Here is a video of my bike with Seans kit. Its 119.6, I am losing about 4 hp with the heavy RC wheel, so if I had a stock wheel, I would be 123-124.

https://www.youtube.com/watch?v=-jIpfPeo8Sw
 
First of all, the only usable part in a stage 1 kit is the needles. So what all did he "put" in there? If he did the complete stage 1 kit, you halfway to a stage 7 kit....or Seans Muscle jet kit which is a hybrid kit.

Do you have a full aftermarket exhaust? It doesnt matter what kit, but you dont really get benefits without a full aftermarket exhaust.

Regardless of what kit you use, you will need air correctors. Stage 7 springs (If you dont have them, they are part of the stage 1 kit) You will need to drill the slides (if they werent drilled with the stage 1 kit, and they are part of the usual stage 1 kit), stage 7 needles, either aftermarket pod filters and catch can, or Seans muscle jet filter lid (and you use the stock airbox), and the barbed oil filler lid (that will T into the catch can, or the stock air box for Seans kit), and jets, probably 147.5's thru 152.5s. Some people will run a bigger pilot jet (40, instead of the stock 37.5)

Me personally, I like Seans kit, it seems to have better midrange than the stage 7 kit.

Here is a video of my bike with Seans kit. Its 119.6, I am losing about 4 hp with the heavy RC wheel, so if I had a stock wheel, I would be 123-124.

I don't know what he did. I don't know anything about this stage 1, stage 7 kit or any kit...the only kit I know is how exactly to eat a Kit-Kat. I don't know what to do or how to tell what he did, or what to look for to find out, or anything, this stage kit stuff is new to me.

He may have done the complete stage 1 process, but I am not sure, that was 10 years ago, and I wasn't involved in maintaining my own bike at that time. I do not think that I have full aftermarket exhaust, but I do have Supertrapp Slip-ons, but I guess that doesn't help.

What do you need me to do in order to find out what I have in my carbs? That whole middle paragraph is completely foreign to me. From catch can to air correctors to the 147 152, I have NO clue what that means.

So, I'll be working on these carbs tonight. I plan on disassembling one a day, and determining what I need for parts for that carb. I'll soak them and clean them thoroughly to prepare to put back together, after I do that for each carb, I'll order the parts and re-assemble and put it back in the bike.

So, what do you need pictures of in order to determine what I need to do, what I have in those carbs and what I'll need to purchase? I'm looking to get this bike running well, be dependable, and SNORT like it was made to do... I don't want to spend hundreds unnecessarily to gain another 4hp or anything like that, but I do want to get this thing running HOT.
 
You need to read and understand the stickies in the carb forum.

How to change main jets will walk you through removal and installation

Carb rebuild by NaughtyG covers complete teardown and rebuild.

Vmax needles will help identify what needles you have.

Mikuni vs Dyno jet will help you identify your jets

Setting dry floats on the bench teaches you how to set the floats.

Measuring wet float level walks you through verifying the floats are set correctly

How to adjust boost cable will teach you just that. Takes just minutes.

And finally, how to synch your carbs cause that will need to be done too.

It's alot of info but it's simple stuff and you need to know it if you are digging in.

When you tear down, you can share photos of the slide springs, slide hole, needles, jets, and top of the carb mouth so we can help identify what you have.

You've got to do your homework on the stickies so you understand what all the parts are and can communicate better with the forum and do the work correctly

Sent from my SM-G900V using Tapatalk
 
So with slip ons, you can stay primarily with the stage 1 kit, that will cut down on cost, and we can help remove or swap parts to get it running like it should be.
 
Back to the bike.

Here are some pics of the first carb taken apart..

Before I forget, I need to get one of the screws that hold on the carb "boots" or whatever you call them.

Also I am missing one screw that goes on the CHOKE assembly...it's the one that is attached to the Choke lever.....

So my question is this, what do I need to order? I need to get the Max up and going. Take a look at these pics. I will order the same for all 4 carbs..

O-ring missing from Fuel Air Mix assembly, so that's needed.. Check out the diaphragm needle. I know some was mentioned with the whole Jet Kit Stage 1 parts, I believe I had that done... can anyone tell?

Big thing is, what are your recommendations if this is just the first (carb number 2 i think)..for replacement parts? I just got back from a surprise birthday vacation to Colorado for 2 nights, it was a blast.
 

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Back to the bike.

Here are some pics of the first carb taken apart..

Before I forget, I need to get one of the screws that hold on the carb "boots" or whatever you call them.

Also I am missing one screw that goes on the CHOKE assembly...it's the one that is attached to the Choke lever.....

So my question is this, what do I need to order? I need to get the Max up and going. Take a look at these pics. I will order the same for all 4 carbs..

O-ring missing from Fuel Air Mix assembly, so that's needed.. Check out the diaphragm needle. I know some was mentioned with the whole Jet Kit Stage 1 parts, I believe I had that done... can anyone tell?

Big thing is, what are your recommendations if this is just the first (carb number 2 i think)..for replacement parts? I just got back from a surprise birthday vacation to Colorado for 2 nights, it was a blast.

Check the top or bottom of the page -BRC carb shop and contact Dannymax for your parts- I would suggest you get the allen head screw sets he sells for the "caps and bowls" also- makes next time so much easier.

In the 3rd and 4th pic you are missing an o-ring for the a/f mixture screw. Probably still in the carbs.
Also I would not reuse jetblock gaskets and fuel bowl o-ring gaskets.
Check the rubber tips on the float needles for wear.
Your rubber stoppers in the top of the jetblock do not look all that great either.
 
1. Looks like you have old gas in the carbs judging by the stains on the paper towels. Fresh fuel doesn't typically leave yellow stains everywhere.

2. Stick a straw from an aerosol can in the hole in the carbs where you removed the AF screw. See if the O-rings are still in there. I'd be surprised if they were not. A straw from a WD40 can works well for me. Blowing air down thru PAJ1 sometimes helps too.

3. I would order all new O-rings. I typically re-use the float bowl gasket unless it is physically damaged or totally flat.

4. Do the rubber plugs from the jet block fit tight? If not, soak in gasoline overnight and see if they fit tight after that. If not, buy new. They are not cheap.

5. Check your diaphragm for pin holes. Hold it up to a light and very lightly stretch. If any holes, buy new. A whole slide assembly is expensive. Some guys have had luck replacing just the diaphragms which, is much more reasonable.

6. I didn't notice the coasting enricheners in your pile. They look like mini diaphragms. Check those for pinholes/damage.

7. Unless you have a Canadian bike, those are not stock needles. I can't tell by looking at the jets what you have there. Would need to see close up photos of the heads.

8. Double check the pilot jets pulled from the jet block in the float bowl. They need to be clean.

9. Best bet is to also replace the jet block gaskets. I got away with reusing them once or twice but I only considered it because they pulled off perfectly clean. If there was any tearing of the gasket, don't consider it. Even if there wasn't, I would buy new if your budget allows. No sense in doing all this work and putting questionable parts back in!
 
In the 5th and 6th pic the paj (37.5) that came out of the jetblock under the smaller rubber plug is the most problematic as it has the smallest hole- be sure you get that clear.
Those are Canadian needles and i have mine on the 1st notch from the blunt end with a 1/2 step washer underneath the clip.
 
1. Looks like you have old gas in the carbs judging by the stains on the paper towels. Fresh fuel doesn't typically leave yellow stains everywhere.

2. Stick a straw from an aerosol can in the hole in the carbs where you removed the AF screw. See if the O-rings are still in there. I'd be surprised if they were not. A straw from a WD40 can works well for me. Blowing air down thru PAJ1 sometimes helps too.

3. I would order all new O-rings. I typically re-use the float bowl gasket unless it is physically damaged or totally flat.

4. Do the rubber plugs from the jet block fit tight? If not, soak in gasoline overnight and see if they fit tight after that. If not, buy new. They are not cheap.

5. Check your diaphragm for pin holes. Hold it up to a light and very lightly stretch. If any holes, buy new. A whole slide assembly is expensive. Some guys have had luck replacing just the diaphragms which, is much more reasonable.

6. I didn't notice the coasting enricheners in your pile. They look like mini diaphragms. Check those for pinholes/damage.

7. Unless you have a Canadian bike, those are not stock needles. I can't tell by looking at the jets what you have there. Would need to see close up photos of the heads.

8. Double check the pilot jets pulled from the jet block in the float bowl. They need to be clean.

9. Best bet is to also replace the jet block gaskets. I got away with reusing them once or twice but I only considered it because they pulled off perfectly clean. If there was any tearing of the gasket, don't consider it. Even if there wasn't, I would buy new if your budget allows. No sense in doing all this work and putting questionable parts back in!

Alright. I am making notes of your notes and will continue with the disassembly and cleaning of the other 3 carbs. The orange stuff isn't old gas, it is the carb cleaning solution I used for my metal carb parts. I read yesterday though that Yamaha doesn't recommend using that caustic solution for the carb parts....oops.. I'll try to do the next one without it.

Anyways, I'll make notes of what parts to order for each carb as I go through them, keeping the parts in bags for each carb and cleaning them thoroughly. When I'm done I'll see what I need and order the shared list for all 4 carbs, so they all get the same new stuff.

The O-ring for the AFM screw was NOT in the hole when I looked. Keep in mind I did this 2 yrs ago and that was my first time....so maybe I lost it, who knows. Either way, I am thinking I need a whole new AFM screw assembly, they are in rough shape.

I will try to take close up pictures of the jets. The pictures shown are of POST-CLEAN. I use a bicycle brake or shift cable and separate one of the strands, and use that to make sure that the little jet screw from the jet block is clear.... that is a TINY hole, but the others are much larger by comparison....

So, I'll take notes for this carb, bag it up and move on to the next and clean it all up and take pics again, same with the last two.
 
Just my $.02 in..
If you have a Harbor Freight near you, this is great for cleaning your carb parts and body, and you can use it for many other cleaning situations, other than the bike.

http://www.harborfreight.com/25-liter-ultrasonic-cleaner-95563.html

I cleaned my carbs 6 times the conventional way (I thought I did a good job).
1st bath, solution started out crystal clear, ended up looking like mud.. It removed shit, that scrubbing couldn't get clean.

Just something to consider.
Good luck with the repair.
 
Alright. I am making notes of your notes and will continue with the disassembly and cleaning of the other 3 carbs. The orange stuff isn't old gas, it is the carb cleaning solution I used for my metal carb parts. I read yesterday though that Yamaha doesn't recommend using that caustic solution for the carb parts....oops.. I'll try to do the next one without it.

Anyways, I'll make notes of what parts to order for each carb as I go through them, keeping the parts in bags for each carb and cleaning them thoroughly. When I'm done I'll see what I need and order the shared list for all 4 carbs, so they all get the same new stuff.

The O-ring for the AFM screw was NOT in the hole when I looked. Keep in mind I did this 2 yrs ago and that was my first time....so maybe I lost it, who knows. Either way, I am thinking I need a whole new AFM screw assembly, they are in rough shape.

I will try to take close up pictures of the jets. The pictures shown are of POST-CLEAN. I use a bicycle brake or shift cable and separate one of the strands, and use that to make sure that the little jet screw from the jet block is clear.... that is a TINY hole, but the others are much larger by comparison....

So, I'll take notes for this carb, bag it up and move on to the next and clean it all up and take pics again, same with the last two.
Guitar string works well for that paj also-There was listed on a thread a complete a/f rebuilt kit pretty cheap. You might try a search on it.
http://newmotorcycleparts.net/fuel_...ious_O-Rings_Specific_to_Mikuni_Carbs----part #4632
 
ok here are some more pics of carbs 3 and 1.... one FAM screw broke the tip, Orings are shot on all, will need new those. Rubber stoppers in jet block aren't fitting tight... what the price on them?

Also the jet block screws dont seem to be stainless...its like they are corroding a bit in there...that's no good. most jets seem to be clear though so far... well here's the pics in no particular order.
float gaskets have been good so far... even Orings seem ok.. well the one next to the FAM screw... if Orings look good, how does a guy know that replacing is necessary.... same with the jet block gasket and also enrichner (choke?) gasket.... they seem ok so far but re-using them?

I am trying to replace all screws with machine stainless... that's like 60 bucks to do all of them just there... damn! but these BUTTER SCREWS SUCK!!

see the fuel line intersection piece? there's a oring on the bottom of that..totally shot...

has anyone else replaced the jet block screws with stainless and had issues with corrosion within float bowl?

pic 8 i tried to show the injured diaphragm....it's not a HOLE, but the rubber part is worn out and you see the mesh material underneath....

oh yeah, getting the springs out of the FAM isn't easy. Air has done the trick by shooting air into the slanted hole that leads out to FAM...
 

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carb number 2

look at all the crap in there. overall 2 FAM screws were broken, the ends broke off...
I need to replace the little diaphragm thing in one of the carbs cuz I forgot to remove it before soaking...now that is destroyed, damn that stuff is tough on non-metal.

jet block jets, the little one INSIDE is in rough shape.. i can upload post-cleaned up pics as well.. anyways.. dang.. this last one, rough shape..
 

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