i have a k&n lunchbox airfilter (one filter two holes)  and i also have a yosh exhaust.  I looked at the jetting and it recommended going to 150 mains, but i searched to see if i needed big round or small round and found nothing about that, but i did find that some people say to use 135 or 130 mains instead of a 150.  what size would be the best for the bike.  150 or alittle smaller?  thanks, oh ya do i buy big round or small round.  thanks.

pre 2001 and 2001+ take different settings.

look here for jet setting for your bike:
http://www.gstwins.com/forum/viewtopic.php?t=12929

The 94 takes a large round mikuni main jet. 130 or 135 is if they had a K&N in the air box.
Cool.
Srinath.

thanks guys, i checked all that stuff on the faq's page.  i saw to run with 150 mains with the set up I have but the i searched to use big or small round and found that people used smaller with K&Ns but it sounds as though smaller with K&N insert and 150 as directed in the faq's page with a K&N no airbox.  Thanks. time to get this bike running again.

I use 150's on my EX500...but that bike's putting down 70rwhp...I can't see a GS with just a filter and exhaust needing that much fuel.

At any rate, it doesn't matter what size anyone recommends.  You change jets until the bike runs propperly.

Quote from: makenzie71I use 150's on my EX500...but that bike's putting down 70rwhp...I can't see a GS with just a filter and exhaust needing that much fuel.

Cool.  What'd you do to an EX500 to get that much power out of it?

Quote from: makenzie71At any rate, it doesn't matter what size anyone recommends.  You change jets until the bike runs propperly.

?  If he's got the same stuff on his bike as 15 people before him, wouldn't their recommendations for what jets work best be the best possible advice to follow?

jeff

Quote from: Jeff PCool.  What'd you do to an EX500 to get that much power out of it?

Mostly head-work.

QuoteIf he's got the same stuff on his bike as 15 people before him, wouldn't their recommendations for what jets work best be the best possible advice to follow?

Starting point, only, but not precise.  Engines are like people...they all like and want different things.  They're affected by weather and season, how it was "broken in", how good the ignition system is working, altitude and about a dozen other things.  You should never expect to use someone else's settings and get it perfect the first time...probably get pretty close.

My last EX, for example, had KN pods and an old-school yosh exhaust.  Other bikes with that setup were using 132's.  My bike required 138's to run "perfectly".  Finding 138's was a mild pain in the ass...

Quote from: makenzie71

Quote from: Jeff PCool.  What'd you do to an EX500 to get that much power out of it?

Mostly head-work.

QuoteIf he's got the same stuff on his bike as 15 people before him, wouldn't their recommendations for what jets work best be the best possible advice to follow?

Starting point, only, but not precise.  Engines are like people...they all like and want different things.  They're affected by weather and season, how it was "broken in", how good the ignition system is working, altitude and about a dozen other things.  You should never expect to use someone else's settings and get it perfect the first time...probably get pretty close.

My last EX, for example, had KN pods and an old-school yosh exhaust.  Other bikes with that setup were using 132's.  My bike required 138's to run "perfectly".  Finding 138's was a mild pain in the ass...

i guess thats why the factory runs all the same jets, thanks though.

Quote from: 94suzuki500i guess thats why the factory runs all the same jets, thanks though.

That's also why no carb'ed bike EVER runs perfect from the factory.

They are all going to run a bit different, but you finish your jet job by fiddling the air screws and float level and needle. Mains and pilots you leave alone. They are all a shade different, but not so far off that we need everything different.
The 150's in your EX ... oddly a larger motor with same carbs will need smaller jets not bigger ... air velocity is what sucks the fuel out. Bump up the air flow and velocity goes up, venturi vacuum goes up with it and more fuel comes out. I have seen many modded motors use only 1-2 sizes smaller jets. I have tested the jetting with a O2 sensor on the roads. 150 is a fair start for a stock GS as is 40 pilots and 1-2 washers and 2-5 turns on mix screw and floats +1 to -2 mm ... I jet them to 1 washer, 3 turns and float at the gasket level send them off and people usually dont ever have to touch it after.
Cool.
Srinath.