What size mains would I use if I am using a k&n lunchbox but stock pipe?

check faq for stuff... depends on your year.

Well nothing works wellreally with that combo... so we are SOL... but try 145 or 142.5...
Cool.
Srinath.

Thanks srinath,

that explains why that combination wasn't included in the FAQ...  Sounds like it's time for me to get off my cheap arse and buy the full system.

I talked with the mechanic at the Suzuki dealer here in Seattle(Aurora Suzuki) and he said that the srinath formula would run  too rich.  He said that they always keep the pilot stock and with the addition of an OEM size  k&n to the airbox would probably keep the mains the same but shim the needle 0.5mm.  And with the k&n lunchbox and a full exhaust would shim 0.5mm and go up just one main size.  Oh yeah, and 3 full turns out for all combos.

If you say that your jetting method is bulletproof then I will have to agree.  I'm sure you have had much more experience with gs500's than he.  I just thought you might want to know what some other people are suggesting.

Peace

You can do with a slipon just as well... anyway pilots ... yea I heard it all... they are just swallowing the company line... kits dont come with pilots, mainly cos the market is so small for bikes that need pilot change, and the aftermarket needs to tool up and make it and put funky numbers and some weird ass code on it... too much work... so they trash the idea of swapping pilots. Wanna stump them... call them and say your GS is canadian... and if they recomend the same thing as the US bikes ...say "but mine already has bigger pilots in it... should I go to smaller pilots that work so well with your kit in my american friends bike???" They cant have it both ways... either the US bikes are correct or Canadian... which will work with their setup... mystery solved. US setup is shaZam!... strangled by EPA... toss the 37.5 and put in 40's. There might be a way to get it all sorted right with 37.5's ... heck I have not found it.... running a higher needle and a shade higher float level takes care of it... sorta ... just response when you snap throttle open is a bit soft, and sometimes it feels rich when you shut the throttle... it wants to die ... but its useable... while the 40's are on the way  :lol:
Cool.
Srinath.

Quote from: DomThanks srinath,
I talked with the mechanic at the Suzuki dealer here in Seattle(Aurora Suzuki) and he said that the srinath formula would run  too rich.  He said that they always keep the pilot stock and with the addition of an OEM size  k&n to the airbox would probably keep the mains the same but shim the needle 0.5mm.  And with the k&n lunchbox and a full exhaust would shim 0.5mm and go up just one main size.  Oh yeah, and 3 full turns out for all combos.

If you say that your jetting method is bulletproof then I will have to agree.  I'm sure you have had much more experience with gs500's than he.  I just thought you might want to know what some other people are suggesting.
Peace

Dom,
Srinath's method is sound.  I've tested it at the track.  My local Suzuki dealer also freaked when I bought jets.  He said that 130's with the K&N RU-2970 filter and a stock pipe would be horribly rich.  I tuned it by ET at the drag strip and ended up at 145 mains with the stock pilots and stock can.

I drilled four holes in the stock can and it went a bit lean.  Then I added a supertrapp slip on (stock header) and am at 150 mains.  I think it's still lean (that open supertrapp and K&N really flow well) so I'm going to try to make the races this Wednesday.  

Don't worry that your dealer freaked..  Mine did too and he was wrong.  Put that K&N on and install some 140-145's and you'll be good to go.

Lean with 150's ... OK maybe your floats are a shade low or somehting... and you have stock pilots still... that might be why its lean especially down low. #4 washer under needle ... you have those I presume... else put them... very much needed. Even in canada in winter 152.5 cost me 700 rpm up on top... go rich 1 size and its like you fell off a cliff. If you are 1 size lean its very hard to tell, 1 too rich and its obvious ... yea tried 42.5 pilots as well... lousy take off's are the result... I have tried Setting  floats 2 mm high as well... you shut the throttle and the bike will wanna die ... unless you blip the throttle a few times... you'll come to the same conclusion...150/40/1 #4 washer, 3 turns and floats at top of float bowl is about the only combo that works... OK yea air screw fiddling or washers are sorta flexible... the rest is nearly ideal.
Cool.
Srinath.