Rider123's new Jet kit!!!(ok, maybe not)

[rider123]

I was thinking of making my own "jet kit" as a stepping stone between a full stage 1 and stock. The reason for this is to keep most of the gas milage of  the stock setup(and less temp/weather sensitive) while giving myself a good chunk of HP boost (7-9?). For example here is my ideas on my new slip on from Muzzy coming in the mail:


2G Bandit with OEM air filter
Muzzy slip on
Main Jet: 105
Pilots: 15
Mixture screws: 3.5 or so
Snorkle out, no holes in box
3 or 4 shims.

or maybe Snorkle in for the low speed "velocity stack" effect but with say 5 to 10 3/8th" holes drilled into the airbox ala Ivan's kit style. I have a few questions.

1. How much bigger is the airbox hole with the snorkle out as compared with the snokle in? Say 1.5 inches with it in, 2 inches when out?(Manual in mail)

2. Could this setup be "fine tuned" by leaving the snokle in(or out) and adding 1 hole at a time? Shimming or mixture screw turning as nessesary?

3. Which is better? Leaving the snokle in for better low speed performance  and adding holes so the airbox can get more air as nessesary or leaving the snokle out completely and no holes? Or any combo of both?

4. Am I crazy?

5. Is it better to just throw the whole idea in the garbage and go with the stage 1 and disregard any fuel milage savings altogether. Although the cost of this project is only about 20 USD for the main jets.


Any advice? thoughts? Estimated HP boost?

[jwalters]

The reason for this is to keep most of the gas milage of  the stock setup(and less temp/weather sensitive) while giving myself a good chunk of HP boost (7-9?).

I see your point, but your weather sensitivity is curred by richening the mixture, which also, lowers milage.  In other words, you can't have your cake and eat it too.  Knowing that you willl take a milage hit whether you get a jet kit or make your own kit, I interpret your question as how to minimize milage loss as you increase power/ decrease weather sensitiivity.

If I was in your shoes, I would shim the needles with 1 shim and turn out my mixture screws 3 or 3 1/2.   IMO, the minute you decide to start swaping jets and drilling holes in your box, you should get a kit from dale or ivans.  Unless you WANT to spend years perfecting your mixtures at different throttle positions, which you might as a hobby I don't know, buying one of their kits is the way to go.  

I remember when I first got my Ivans kit, I was very impressed with the shape of the needles, after talking with the guy at Ivans I realized how much time and effort they put into their product.  I've heard the same thing for Dale of course.


As far as going with 3 or 4 shims, that seem WAY out of control.  I wouldn't recommend going above 2.  As I tried two for a while, and I was fouling plugs, and getting worse milage.  And this was with a exhaust that had no baffles.

If you are after 7-9hp, that's about what I got out of my stage 1, maybe a bit more, but when you start talking about 1 or 2 hp increase versus 1 or 2 miles per gallon, you are talking about fine tuning that may or may not be achieved.  What I mean by this is, you might be right on the money for a month during the summer, and then when fall hits the cold air throws your setup a bit out of wack, and  your a few mpg from your desired...

So my take home message, IMO of course, is get a jet kit, these suckers dont' have FI (someday... ) so real fine tuning isn't practical unless you are racing or you simply love to pull off your carbs and smell like gas.  The chicks do dig it, like a colon almostl.  But I digress,  a stage 1 kit doesn't make that much different in milage, and the milage you do loose will be returned 10 fold in the way your bike performs.

My $.02.  Hopefully they weren't 2 cents you already had in your pocket, but I tried.
-j

[rider123]

Good points. I wasn't implying that my bike is weather sensitive now. Also the arbritrary number (7-9 Hp) was just thrown out there as usually just sticking on a pipe with no jetting changes gets you around 5 usually. What I was wondering more for a fun weird project(I like to smell like gas   ). I guess you could say it would be a stock plus jetting. If you're saying this could be achieved by shims alone all the better and less work! Also I am willing to take some MPG hit otherwise I wouldn't bother!

But for example from a High of 50 MPG stock(105 HP) to 39 MPG(118 HP) is alot however 50 MPG to 45(112 HP or 42 MPG(115 HP) (for example) would be fine. Weird I know but fun none the less.

[jwalters]

Sure I understand, its a tradeoff and knowing where to draw the line is a matter of opinion. If nothing else, you might learn something by not getting a commerically available kit as long as you know what your in for, which it sounds like you do.  

That said, I wish I would have done my stage 1 kit years ago, I waited till this past summer for some reason.  I should have done it before I got the Givi rack, and all the other add on stuff.  Afterall, it was, without question, the best $100 you could spend on the bike.  I know Red01 and PeteSC have pulled their hair out for years stressing this point, too.  

But now, i am turning that bike into a race-only bike, so I wish I would have gone with the stage II kit with pods.... oh well, can't predict the future.

The other thing is, if you swapped main jets and shimmed the needles correctly, you could follow the Ivans kit pretty close as far as the idle mixture screws and air box modification is concerned.  That configuration would get you pretty close, slight adjustments might have to be made since you are using stock needles compared to the tapered needles provided in kits.  And when you hold the two types of needles up to each other you see just how different they really are.  But you could get pretty darn close to their performance, without having to buy anything but new mains.

[solman]

Is it better to just throw the whole idea in the garbage and go with the stage 1 and disregard any fuel milage savings altogether. Although the cost of this project is only about 20 USD for the main jets.

Dale and Ivan have both tried different things as in snorkle in and out, K&N filters, etc.  You aren't getting a $100+ worth of parts, you are paying more for the research and hard work that they put into it to achieve the best results.  Also my gas mileage actually went up a little bit with my exhaust and jet kit.  Depending on how you do the power gain, it can often give more power and better gas mileage.

[rider123]

Please, I wasn't implying that Dales or Ivans kit wasn't worth the money. On the contrary, I will be buying one of their kits without a doubt this spring. I was just brainstorming to see if I could try and build a stepping stone to a stage 1 for fun. It might be a good experiment for those that want to clean up the stock jetting but not do any significant changes to the stock setup in case they want to go back. Since the engine on this bike is almost legendary in the things you can do to it, I think it would be a fun experiment to really get a sense on how and why the bike is jetted as it is and how it can be improved with only minor adjustments.

As far as stage 1 or stage 2 I was thinking of just going stage 1 but you people make it so hard to decide with your HP improvements!! Damn you!  

[PaulVS]

I believe you'll want to go with 110 or 112.5 mains, not 105.

Also, 4 shims might be a little much.  I'd do 2.

Also try 17.5 pilots while you're at it. (A/F screws at 3.0 turns if you do.)

That should be a close approximation of any stage 1 kit.

[rider123]

Well my Muzzy slip on came today. Wow! is this thing light! It probably weighs about 7 pounds or so I'll weigh it when I get home and post some pics. Seems good quality for the bottom line muffler and is nicely polished. Comes with a centre stand stop which I'm glad, as I was worried about. Exhaust port WAY bigger than the teeny tiny stock muffler. Although my Yosh exhasut on my '84 GS750EF had a bigger exhaust port than the stock exhaust!

edit: Bummer!!! There is a 4 inch scratch on the bike side surface of the pipe! I'll call and see if I can get some money refunded for taking the time to polish it out myself. Looks like muzzy's fault not J C motorsports.

[Red01]

Here's what I'd do as a stop gap until it was jet kit time...

Two shims on the needles. 3 turns on the mixture screws. Leave everything else alone until jet kit time.

But as already stated, you'd be real close to Dale's Stage I with 110's & shims... in fact, that's pretty much what you would have, less the timing advancer, and there's a free way to do that, too. Well, Dale does give you new allen headed float bowl screws, too.

Click here and scroll to the bottom of the page for the free advancer.

[rider123]

Wow that's cool. I guess you could "McGuiver" a timing advance yourself, in fact in someways it is better as you can fine tune the advance instead of just having a fixed 5 degrees. Maybe say 3 degrees is better. I think if I mount the can myself I'll just shim the carbs the recomended 2 shims that you guys suggested(leave the airbox and jets alone) and keep the mixture screws at 3 turns out untill I get a proper jet kit. Interesting what you can do with this bike. Has anyone ever tried the "McGuiver" version of the timing advancer? WHat if you basically did Dales kit without the advancer? Is there a problem running it without the advancer or do you just lose a couple of Ponies up top?

Ill post some pics of my exhaust here when I get the camera going:

[Red01]

Actually, the advancer might cost you a small bit on top. It's actually much better at improving throttle response and a mid-range gain... and that's where most of us will notice change since that's where we spend more time.