BannedCR500Riders.com

I have a 94 CR 500 that has a 90mm bore rather than the stock 89. Right now I just put in:

The following stock settings:

170 main
55 pilot
Stock Needle (1368) in the 3rd clip
And 1.5 turns on the air screw
I am also running the stock pipe and muffler on this 500
I mix my fuel 32 to 1 on pump 91 octane.

I guess technically the displacement is closer to a 502

Any ideas if I should adjust jetting based on this slight bump in displacement? I ride at 900 feet above sea level and it's been 50 to 60 degrees lately.

I did drop in a new 90 mm piston and thoroughly cleaned the carb. It just doesn't seem as responsive as my other 500 which is a 97 with a stock bore where I run the same settings except for a 2nd clip position on the needle because I have a Gnarly pipe and Turbine Core silencer.


I would appreciate any thoughts.

Thanks ,

Cody

don't think you will need to compensate for the bigger bore, have you run it long enough to get the rings seated and the piston to loosen up ? does it lean surge at idle? rpm hunting up and down?

The bore dosen't matter, its what the motor wants that matters and not so much the mix. Why not 50:1.

A 1468 needle / DGJ seems to be liked very much. Or try the 2nd clip with the stock needle.