does anyone know what size jetts came in my 99 900rr the ones that are in there are 116 and it seems to run lean but with the 118's it seems to rich i have a two brothers full system and 4 degree timing advancer

 

I believe it was 40 and 120 for the stock. Johnny

 

thanks JOHNNYH so from what i gather then the ones i have in are smaller . i always thought that with a rejett you go bigger ? any thoughts??

 

would depend. the purpose to rejet your bike is to improve the fuel air mixture. If you increase the amount of fuel being squirt in your bike you will need more oxygen aswell. If you are running lean you need bigger jets and or less oxygen, but why restrict the oxygen right? the opposite applies if your running rich. My bike runs a little rich. Keeps the engine cooler. Id rather run rich than scorch my engine.