Hi! Can anyone please explain why the stock main jet sizes vary so much? You U.S. guys usually seem to have main 145 as stock, but mine is only 125 (Sweden, Europe). I'm at sea level and temperatures between 15 and 30 degrees Celsius (60-85 F) during riding season.

I'm in the process of converting to the Ryca bobber (with open K&N type air filter and short reverse cone muffler) and Ryca's jet recommendations are 52,5 pilot and 150 main, but this is based on that stock are 52,5 pilot and 145 main, so with my stock 47.5 pilot and 125 main I'm not sure where to start out. Maybe step up one or two sizes from my stock first (and do the spacer mod)? Any other suggestions? Thanks!

verslagen1 wrote on 08/20/14 at 08:05:26:


I'm pretty sure they are the same scale.

The 125 main jet ssems to be stock on CA (Canadian?) models as well. Since the bikes seems to be pretty much the same otherwise I find it a bit mysterious...

Serowbot wrote on 08/20/14 at 08:47:47:

While we normally assume the CA is calif... my '96 came with a 145.
And I think I've seen the same with a few others.

So I think in this case, CA means Canada.

yep, they're in calif. as well.

Thomas Högberg wrote on 08/20/14 at 14:58:41:


I see a pattern here  , mine is also a -97 and imported from Germany. Thomas, have you changed anything (air filter and/or exhaust) and if so what jets are you using now?