Muscle Jet Kits

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one2dmax

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Start putting your info in here so everyone can find it in one place.

This is the original info about the first kits and pricing. Everything is the same but we have had many more kits sold/installed with excellent results. 95% of most kits make over 120+ rwhp while still maintaining 38-42+ MPG. More mid-range with same top end as stage seven.

We have had a few bikes dyno into the 130's with this kit. The typical bike will make mid 120's.

I do not normally recommend this kit for slip-on or stock type headers as they are really choking the flow down. A full header is best for this.

>>>>>>>>>>>>>>>>>>>>>>>>>
Here is some info I have for you and a picture of our earlier design - the basic setup now is the same just different filter (size).


<<<<<<<<<<<<First Email with dyno results>>>>>>>>>>>>>>

Well, got the chance to do more testing yesterday and some road testing today. Here's what we found out:

We have three bikes so far with our new jet kit and a fourth that we were short some parts that didn't get a chance to get finished (it is now finished and runs very well).

First bike is a 2000. It has the quieter Hindle (super sport?) exhaust system and is otherwise stock internally. He was able to tune his bike to 121 HP with our new kit. He is using Factory Pro Titanium needles as well. His v-boost is being used in conjunction with a t-boost unit. His bike runs well and clean through the entire rpm. He has struggled for a long time to get his bike to this point. I believe his bike started at around 110HP in stock form.

Second Bike is a 1994. When we received this bike it had Hindle slip on's on it (which are for sale) and was a relative dog. We were not able to get a dyno in that form though. Currently he has a Kerker header with a two-brothers carbon fiber muffler made for a TLR 1000. We adapted this muffler (and will be offering this service) recently and would be about equivalent to the 2" standard Kerker muffler. With our tuning we were able to get his bike to 123 HP 8-.5 Torque and it is running great. He is getting 40 mpg including some long high speed test runs that probably killed a mile or two off of it.

Third bike is a 1999. It was received with a stage seven installed per instructions and Kerker header with comp baffle. The bike dynoed a very respectable 124 HP as received but with a simple jet change (leaner) jumped to a very nice 127.27 HP and 80.6 Torque. We went a bit leaner on Saturday and got the fuel curve nearly perfect (in our opinion) except a very touch rich in the mid (1/2 clip maybe). Power dropped to 125.8 HP and 79.4 torque. With this baseline we decided to swap to our kit. We completely removed the stage seven and installed out kit. The new dyno showed 125.03 HP and 81.87 Torque. A 2 HP loss in top power but 1 lb torque increase BUT there was an almost 10lb increase in torque in the midrange. However, the test in not 100% valid as the other tests had the v-boost on full time where our kit had it functioning normally. The best part was i got 44 mpg with the new kit and it runs great.

<<<<<<<<<<Second Email with Pricing>>>>>>>>>>>>>>>>>>>>

The "deluxe kit" will run about $240 but will not have any core needed (or save some with your core which is preferred). It will include a new airbox lid with new flat K&N filter already installed. It will include 4 jets of each size from 155 - 165 (six sizes - 155, 157.5, 160, 162.5, 165, and 177.5 for the PAJ2 if needed) which will give a very nice range to select from. We will try our best to help you get close (tell you what combo's are currently working) with your jet size to start with. It will also include new springs and air correctors as well as the proper bit to drill out your slides. It will NOT include new needles. I can get these for an additional cost but so far the kit is working very well with the stock needles. There is also a new vent breather hose and adapter included in the kit. I can offer this in a true braided setup but they can get expensive quickly.

For a less expensive kit you can deduct $20 for sending me your old airbox lid (you would get a used one back too). So you can get this kit down to $220 if you send your old lid. Don't forget to add some shipping ($20 in U.S.) to the price too.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Basic Install Instructions
Here's some quick directions and description of what the parts are doing.

The "T", Hose, and Oil fill cap (replaces the stock cap - don't forget to move over the oring) all will install into the PCV system. Basically when you remove the carbs from the engine you will want to take off that 1/2" hose. Cut about 3/4" off the bottom and discard this chunk. Cut it about 3/4" from where the last bend going up is, install the "T" fitting into that section (upper cut section) aiming towards the rear of the bike, and re-install it back into the PCV system. The black hose will fit onto the barb facing rearward and routed back and down to the new oil fill cap (don't forget to move over the o-ring from you old fill cap). Essentially you are "Teeing" into that system and making it pull a vacuum in the crankcase. This aids in ring seal for more power and economy. I have found that it is sometimes easier to cut all but 2 barbs off of each section of the "T" so you don't have to fight it on.

When installed it will have that rear facing barb right under the carb rack brace with the stub sticking up to connect to the base of your airbox like it does normally.

You can start with a 157.5 main or 160 main if you are using the stock needles. Typically other aftermarket needles run richer so you would start with a smaller main. Either jet size will be close but these bikes do like leaner more then richer. The rest of the install is much like the stage seven. You can drill the slides with the supplied drill bit if desired and change out the springs. This allows for faster throttle response. They will work with out drilling too. You can unhook the v-boost in the open mode if desired or leave it stock (I like the stock position myself but wide open gives a bit more rump sound). Don't enlarge the center hole where the needle passes through but rather the hole off to the side.

The brass air correctors install with the flat side downward into the air inlet hole on the top of the carbs. It's right next to the hole that has a jet in it. When you see the correct hole to install it you can look into the hole and you will see a thin walled brass sleeve down inside there. Put the flat side down and start by hand. You should be able to get it about half way started. Use the small punch that was included to drive the corrector until it is firmly seated which will be well down into the bore.

Don't forget to sync the carbs when you get it all back together.

Sean
 

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I just put my muscle jet kit on my bike so here is a review of my installation.

Let me start out by saying that I am a TOTAL newb to carbs. I have never had the carbs off of any streetbike. I've been into my lawnmower and my dirtbikes carbs but thats about it. Always been afraid of the "black magic/voodoo" it seems to take to get carbs dialed in.

Next, I have to say thanks to Sean for answering my phone call an giving my some tips, and to Mark for answering my questions on the forum here. I printed out quite a few of the stickies in the carb section so I had them in hand to do the teardown. There is quite a bit of good information here. I used Marks thread on replacing main jets. Someone converted it into a pdf and it prints nice. It is attached at the end of the thread and I would HIGHLY recommend anyone doing this without a clue to print that out and have on hand. I also printed out info and pics on how to do the shotgun, set float height, and carb synch, and all of NG's carb rebuild series just in case. All of these were extremely useful to me. I also read this thread: http://www.vmaxforum.net/showthread.php?t=3411 for some background info. And, Sean's first post in this thread is great too. That is pretty much the extent of my bibliography required to get this done.

I must say that it was not difficult at all to install the kit. I went a bit further by completely removing the carbs, splitting the rack, adjusting float levels, clean fuel bowls, doing the shotgun on the bench just because, and then putting it all back together.

Some things I must say to those who have no idea what to expect.

1. Buy yourself some screws for the diaphragm covers! I destroyed one trying to remove it. 5mm x .8mm x 14mm or 12mm
DSC02290.jpg


Make sure you break all the diaphragm screws loose BEFORE tearing the airbox off. It will just prevent getting crap in the carbs if you have to grind or drill a couple screws. I used an impact screwdriver to remove all screws, but I did NOT hammer on it till the last one you see here. A few light taps and it ate the screw. It didn't slip, it just chewed it up. F'er was tighter that a bull's ass in fly season. I slotted the head with my imitation dremel and used the impact again and it worked well enough.

Getting these screws out way the #1 hardest part of installing Seans kit.

2. The #2 hardest part of Seans Kit install was just getting the breather hose back on the barbed fitting down on the engine block between the cylinders. So, if you think you can manage that, you can put Seans kit on your bike.

3. If you've never tore into these carbs I would highly recommend looking over the "Shotgun" procedure. It will help you understand what your doing after you remove the diaphragm covers. One additional not I will throw out there. I you remove the slide completely to drill them, pay close attention to the needle jet assembly to make sure you put things back in the proper order concerning the spring, clip, and existing washer. Also note that the needles have a little "tit" that index it into the slide. Make sure the tit is engaged. Oh, and make sure you pay attention to the black o-ring that the Shotgun directions warn you about. The first time I blew thru the carb the o-ring went flying. OOPS! I didn't bother looking, I had no idea where it went. I found it 2 hrs later and 15' away next to my wash sink :eusa_dance:

4. Synch. Again, directions from this forum are great. I've never synched the carbs before but it was pretty easy. I set up my carbtune by installing the restrictors per the directions while the bike warmed up and slapped it on. It takes a screwdriver with a pretty thick tip to adjust the synch screws. Read the directions and you can't go wrong here. Came home Monday and had no more than 1 hr to button things up and figure out synch for the first time. I had to turn the Idle up to make it run right at first. Once it came into synch the idle picked way up and I had to turn it back down.


The rest of what I have to say concerns going a bit farther than just throwing in Seans kit.

1. Buy yourself some float bowl screws if you plan to remove the bowls. Not quite as bad as the diaphragm screws but I still ruined one. 5mm x.8mm x 12mm

2. I would HIGHLY recommend that you check your float levels. (too bad yankee wasn't here to comment on that one). Mine were all way rich.
DSC02297.jpg


Heres a comparo: Left is what I found in there, Right is what it should be
DSC02295.jpg


Heres a closeup of it set correctly
DSC02296.jpg



3. Pay attention to the way the throttle cable junction comes apart. The sliders inside will only "slide" smoothly and correctly when put back one way. It will fit back together more than one way though. If it is wrong the throttle will bind when the bars are turned full lock.

4. Have a couple of pieces of wood to place the carb rack on. It makes it easier to work on when you elevate the manifold side of the rack up on some little blocks. My blocks were 3/4" thick. Just thick enough to clear all the hoses and stuff on the bottom when the manifold side hit the wood.

All in all it wasn't too bad. It took me a long time but I was in no hurry. I was trying to learn what I could as I went along. Adjusting the floats takes patience as it is way to easy to bend the tab too much one way or the other. Sean's kit was really easy to put in.

Now it is time to fine tune. I hope to get it running right soon.... I put the kit in Sunday night. Too late to test when complete. Only had and hr yesterday (monday) to do some final touches including synch. No test ride yet.

My initial settings are:
160 main
Stage 7 springs
Stock needles, no shims
Did not drill slides yet
A/F screws at 3 turns out.
Live in western PA. Elevation is approx 1200' around here.

The bike fired right up once the bowls were filled. I did notice that when it got hot during the synch it popped a couple times, loudly.

Lots more intake noise with this kit.

Hope it all runs good soon, can't wait for a road test. Hopefully after work today! :punk:
 
My initial settings are:
160 main
Stage 7 springs
Stock needles, no shims
Did not drill slides yet
A/F screws at 3 turns out.
Live in western PA. Elevation is approx 1200' around here.

OK, before my first test ride after installation of the Muscle Jet Kit I ended up going over the mixture screws again. I ended up putting them at 3.5 turns out because when I did the synch on monday it popped through the carbs a couple times pretty hard when at 3 turns out.

Seemed pretty good after that so I just went for a little scoot.

I can cruise at 5K no problem. No breaking up, bike idles ok. Not as smooth as it used to be but it seems fine. Guessing the A/F screws are OK by this??

Bike seems to run just fine from 7-9K rpm, no issues that I noticed.

when crusing around 4K rpm and I wack it there is no hesitation or breakup. it does however seem to take some time to build up speed and "pick up" from this point. Maybe this is where drilling the slides would help? It just seems to lollygag around before it builds up some speed.

Also noticed that when sitting in the driveway, if I throttle up to 6K rpm it starts breaking up. But seemed fine while riding in that range. Any ideas on that?

Thinking I may try shimming the needle just to see if that helps anything.
 
Mike, for you 4K test it sounds like you're a bit rich. Try putting the stock slide springs back in.
 
Mike, for you 4K test it sounds like you're a bit rich. Try putting the stock slide springs back in.

Damn, YOUR FAST!

I will try that and see whats up. Thanks for the suggestion. I just picked up my bag o washers from Sean and was ready to make it even richer by by shimming!

What do you think about drilling the slides? I would rather not. I will try stock springs first and see how that works.
 
OK, my buttometer must not be very sensitive. I did not notice much difference between stock and stg 7 springs. maybe, i mean maybe just a touch better. I think my problem is that I was just expecting it to come on much stronger when I flogged it in 5th at 4K rpm than what it did. Its definitely not slower than it was before!

Anyhow, back to the 6K RPM popping. I must say that I DID ever so slightly notice a very, very tiny amount of popping through the exhaust not carbs, when at 5.5-6K rpm, holding the throttle steady and cruising there, at a very, very small throttle angle. This is the only spot in the whole range I noticed this. And it was so slight that I only heard it if I was really listened. Like hanging off the bike sideways in 3rd gear at 6K rpm with my head as close to the rear tire as possible. Thats the only way i noticed it while riding. But, like I said, I did hear it while sitting still and revving it up to 6K.

Any suggestions on this??:ummm: Still haven't drilled the slides. Like I said, I'd rather not if avoidable

On another note, I saw to BIG boys riding tandem on a harley bagger at a stop sign. I was going past and had to show em a thing or two. DAMN if it wasn't my best wheelie to date. Hung up there real high in first, gassed it enough to where I thought I was gonna loop out (flip over backwards) so I could keep it up into 2nd and hung it out for a while in 2nd. Probably just long enough for em to see me riding of into the sunset on one wheel! They probably could have cared less but I was enjoying myself.

Alright, back to more testing!
 
i had to play with shims to get rid of the low to mid range popping. i used stock spring stock needles and drilled the slides. its a process to get it right i dyno'd mine and its almost perfect the a/f needs a tad bit of tweeking but still ok.
Chris
 
http://www.vmaxforum.net/showthread.php?t=3411
Mkae sure you don't use clear Pex pipe for the breather hose.

:banana:

Right on ID. I read your thread about the install. I even have it listed above in this post as part of my research material. Your experience is the main reason why I want to work through all this before resorting to the drill.

Just got back from putting some miles on it. Stock springs are in there again after Marks suggestion. I'm pretty happy with it except for the mid range issues. The more I ride the more I am able to find the stumble in the mid range. It hits anywhere between 5K and 6.5K. Most noticable while holding the throttle steady or just getting off/or getting into it and easiest to reproduce in 2nd gear. Guessing this would indicate i need a shim in the needles. I will try to do that and she where she is at then.

Thanks to all for the advice so far.:worthy: It just keeps getting more and more fun to ride this thing.:punk:
 
Shim the needles. I didn't notice any difference with stock or short springs. My slides are drilled.

Dale #2592
 
I'm having the same issue at 6K. I drilled the holes and used the short springs. Does the shim go above or below the clip? I have stock needles and there is only one clip position.
 
The stock needles aren't adjustable like the dynojet needles. But u can put in a shim to bring it up a bit. It's been awhile since I had mine apart but if I remember right it goes between the white plastic piece and the "clip". Once you get the needle out and have a look it's easy to see how it goes.

If your mid range is OK and it breaks up right around vboost range shimming won't help you. I had a consistent stumble at starting at 6000 +rpm. :bang head:
Only one thing cured it.....bigger main jet!!:eusa_dance:

Dale #2592
 
Yeah, it stumbles right at 6K, but if I keep on the throttle, it'll pull through and be smooth again at 7K. I'll try a 157.5 main and see what happens.
 
Yup....been there done that. Bigger main needed. Hope the 157.5s are enough!
You should make changes incrementally but based on my experience I'd go to 160s.

I'm running 170s now.

Dale #2592
 
I was going off another members settings. He had 155's and a shim under the needles at 900 ft. He thought I should use the stock 152.5's and be ok. Where are you at in Ontario? I've got family around Lindsey.
 
Ok, put the 160's in and the problem still exists. Just over 6K when throttling up smoothly it will break up and start to backfire. Now there is also a small break up at 4K. Do I need to go richer and shim the needle up?
 
Your problems sound very similar to mine. Here's my story:
I'm near Niagara Falls about 800 ft.
I started out with the 157.5s. Was good except consistent break up at 6000. Went to 160s with a shim. Same thing but then noted a slight stumble at 4000. Put in another shim. Low rpm stumble gone but still there at 6000. Have now just worked my way up to 170 mains. Its good here.:clapping: I haven't heard of anyone else this large but it works for me.

Final settings: HMF header, stock needles with 2 shims, 170 mains, drilled slides, and the short springs. Throttle response is excellent but mileage is down to 35mpg. (I was actually getting around 45 mpg with the 157.5s) I think I'm going to try taking out 1 shim as the weather gets hotter.

Dale #2592
 
Ok, got it almost perfect. 162.5 mains, stage 7 springs, drilled slides, 2 shims under stock needles, 1500 ft. Bike has good power all the way through red line. Don't get into Vboost range as often now. Thanks for the help.
 
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