GStwin.com GS500 Message Forum

Main Area => General GS500 Discussion => Topic started by: rangerbrown on August 22, 2006, 07:28:04 AM

Title: i messed up the jetting, please help this retard...
Post by: rangerbrown on August 22, 2006, 07:28:04 AM
ok. starting over. as i have done somthing wrong and have a new ppe.

to start, i have done back to stock (what ever that is) what is it (2004)

now the mods

K&N drop in, i will be keeping as it works better for me (enough said)
stock headers, but the can is a scorpin (it's realy a strait though pipe) no baffles only packing
it is made for 05 down gsxr 600 (the bolt on style) pictures later (it's SS)

now given than what are your recomened jet sizes? i would like it a little rich to help prolong the life of the engine.

elevation is near 300-400 feet

thanks for the help guys
Title: Re: i need some help, jet guy/gals please
Post by: Turd Ferguson on August 22, 2006, 07:48:23 AM
I've got a K&N lunchbox and a high flow can, but stock exhaust.  I haven't installed everything yet, but my plan was to try 22.5/65/145 and go from there.  If you have full exhaust, you might end up wanting a 147.5 but that is a guess. 

-Turd.
Title: Re: i need some help, jet guy/gals please
Post by: rangerbrown on August 22, 2006, 07:49:22 AM
ok sounds good.

i just found this, very good from "miket"
http://www.angelfire.com/mt2/mikesgs500/rejetting/
Title: Re: i need some help, jet guy/gals please
Post by: Wrecent_Wryder on August 22, 2006, 08:40:57 AM
j7
Title: Re: i need some help, jet guy/gals please
Post by: LimaXray on August 22, 2006, 09:09:19 AM
I have just a lunchbox, 20/62.5/137.5, and 3 turns out.  It runs great, maybe a little lean, but not as lean as stock and it's perfectly smooth.  It seems to me the lunchbox makes a far bigger difference in jetting compared to the exhaust, and the addition of an exhaust usually only requires one step up in size.

Anyway, I agree with Turd's jetting selection for everything but the mains.  I would think you wouldn't need anything bigger than a 142.5 on a '04+ if you're also using a 65 mid main.

It is confusing to pick the right jetting for the '01+ because there isn't much definitive info around about it.  I believe the 01-02 are different from the 04+ even though the are usually lumped together around here.  The 01-02 seem to need richer jetting than the 04's, ie compare Wrecent's jetting with Alpha's and mine, we all have a lunchbox, but Wrecent's has much larger jetting.  Basically, don't use the '01-'02 jetting info for your '04+, or vise versa.

As for removing the float bowls, I don't agree that you need an impact wrench.  I used my trusty Dewalt power drill with a properly size philips head bit with great success.  I put a stack of news paper on the ground under the carbs to cushion them, then put all my weight into the power drill (had the thing pressed up against my sternum) and backed out the screws.  It worked for all but 2, which were the first 2 I tried and didn't use all my weight, but once I figured it out, it worked great.  For those 2, I made the screws into slotted screws with my Dremel and did the power drill method with no problems.
Title: Re: i need some help, jet guy/gals please
Post by: rangerbrown on August 28, 2006, 04:47:38 PM
disregaurd post
Title: Re: i need some help, jet guy/gals please
Post by: bettingpython on August 29, 2006, 09:37:10 AM
At 9k are you at WOT? If less than WOT you could be transitioning between rich mids and rich mains. Dunno on this one since mine is older and uses shims on the needle for my mid range.
Title: Re: i need some help, jet guy/gals please
Post by: rangerbrown on August 29, 2006, 08:25:58 PM
disregaurd post
Title: Re: i need some help, jet guy/gals please
Post by: blue05twin on August 29, 2006, 08:52:01 PM
K N lunchbox filter wileyco with srinath flange my sig has my jets pull's to 10K np  is still a bit rich I'm going to change my mixture screws a bit to 2 3/4 or 3 turns out.
Title: Re: i messed up the jetting, please help this retard...
Post by: domas on August 29, 2006, 09:43:32 PM
Quote from: rangerbrown on August 22, 2006, 07:28:04 AM
ok. starting over. as i have done somthing wrong and have a new ppe.

to start, i have done back to stock (what ever that is) what is it (2004)

now the mods

K&N drop in, i will be keeping as it works better for me (enough said)
stock headers, but the can is a scorpin (it's realy a strait though pipe) no baffles only packing
it is made for 05 down gsxr 600 (the bolt on style) pictures later (it's SS)

now given than what are your recomened jet sizes? i would like it a little rich to help prolong the life of the engine.

elevation is near 300-400 feet

thanks for the help guys

First you need to find out what main jet you need. The stock i think is 130. Try to put 132.5 first, then 135. Increase only one size at a time. Now for the testing you want your bike warm first (~10 minutes riding), then find a straight road or entering highway is also good. Put bike in 3rd or 4th gear, hold at 3k rpm, and open throttle fully. Accelerate like this up to 9k rpm. The bike should accelerate without "missing a beat" or stumbling. If everything is ok You can try to increase jet size, but you probably wont go over 135. Eventualy you should feel hesitation ("flat spot") around 6-7k rpm. After you have settled on a good main jet, raise the needle by adding a shim or with e-clip, also you can put 20 pilots for better warmups.

I have a similar setup, KN drop-in and a full exhaust system, but it is not a super sport, just sportier. Stock main is 127.5. I went for the 137.5 and it was bad. I had to go down to 132.5. Now it is still little rich but doesn't cause any performance issues. Also when it gets a little bit colder it runs better. I'm thinking for the next summer i'll put 130 in the warm days.

If you have any questions you think i might know an answer to, pm me. I will try to answer those.
Title: Re: i messed up the jetting, please help this retard...
Post by: Wrecent_Wryder on August 30, 2006, 03:15:36 AM
B6
Title: Re: i messed up the jetting, please help this retard...
Post by: rangerbrown on August 30, 2006, 05:43:10 AM
no restictor, i think i went buck wild with the the jets i chose and thats why i had problems
Title: Re: i messed up the jetting, please help this retard...
Post by: domas on August 30, 2006, 10:46:48 PM
Really i didn't think that increasing jet one size (2.5) has so much difference. Air box is the main restrictor not the filter in it, so drop in only adds little, let's say one size, and maybe one for exhaust. In your place i would buy 2x132.5, 2x135, couple shims, and 2x20 pilots. And play around with these. Just remember to play with main jets first, as they affect all other jets.