I have an 07 gs500f and I need some advice on some jet sizes to go with. It's got a k&N lunch box and a open exhaust. I've rejeted it once before but can't get to the bike to check what size jets are in it but the last time I had it running it was still lean and trying to run hot. Now that ive lowered my elevation I do not want to even start the bike with too small of jets. Advice?

I also need to source a daiphragm (sp). One was torn during a reassembly.

wiki.gstwins.com  Upgrades -> Rejetting

Upper elevation = lower air = leaner settings
Lower elevation = more air = richer settings

If lean at high altitudes, my initial guess would be to richen a bit more at lower elevations to compensate.

Plug Chops will confirm what wiki.gstwins.com states as a starting point.

Diaphragms are found either on Ebay or an OEM parts reseller like bikebandit.com or your local Suzuki dealer.  Stick with OEM on carb parts otherwise it will run like poo.

Or, you can PM Adidasguy who has a lot of parts.  He's our resident parts extraordinaire. 

I messaged The Budda about this but he hasn't been online since the 16th. And there isn't a referance i've seen for running full open exhaust. :/ and thanks i'll definately hit him up.

Diaphragm is a 24 dollar part from the dealer, just bought one last week. And by open do you mean no muffler?

Pure straight pipe.

Quote from: gsatthebeach on February 21, 2013, 12:15:18 PM
Pure straight pipe.

I'd be interested in hearing a sound recording. Althouth I doubt any mic would give it justice.

Not trying to thread jack but I have a vid with open exh in it

It's loud as sin and sounds like a harley at idle, and kinda ricey up top if I remember right. I ran it around the block when I cut my old muffler off. Loved the sound mainly, lost a lot of power, but with proper jetting I'm sure it just runs better. I gotta do it again soon lol

I think i'm going to go with a 20, 65, 145 set up.

your jet size you have selected is very close you may like to do an ignition advance as well to get extra performance .i take it that you have removed the cat in the exhaust just after where the pipes go two into one . i did 3 degree ignition advance  after trying 5 degrees  and use a NGK  DPR9EA-9 SPARK PLUG ..you may need a 150 main jet but i dont think so even with a open pipe