Rm 85 jetting?

Hey guys i have a 2004 Rm85L with an FMF exhaust and a fresh top end i was wondering if it would be a good idea to jet it due to it having the exhaust or is it really unnecessary? I feel it bogs more then a usual 2 stroke at low rpms so i dont know if its due to it needing bigger jets and if so what sizes should i need? can anyone help please? Thanks

I ran the same exhaust on my sons RM 85 drop the pilot jet down to a #45 and it will run a lot crisper on the bottom end.

Ok cool so change only the pilot jet?

Ok dont quote me on this but i thought with a bigger exhaust you needed more fuel?

These bike's are way to rich from the factory. What does the spark plug look like as far as color?

Edited by moto man rm250

I put a fresh one in the other day and rode for like an hour ill take it off and check and if they run rich from factory thats probably y i feel the bog on low end? Maybe

The warmer it gets the worse it will be your stock pilot jet should be a #50 I would get a #48 and a #45 just to have they are easy to change and are cheap from rockymountain.

The warmer it gets the worse it will be your stock pilot jet should be a #50 I would get a #48 and a #45 just to have they are easy to change and are cheap from rockymountain.

Ok ill definitely do that...just the pilot jet?

I also ran my son's bike with the clip in the second groove on the needle but i would just try the pilot jet first it will make a big difference.

Great thanks

Changed the jet to a #45 what a difference runs way better thanks guys

Anytime glad to help. If you need a little more bottom grunt change the sprokets to 13 front and 48 rear.

Anytime glad to help. If you need a little more bottom grunt change the sprokets to 13 front and 48 rear.

Its funny i have that setup on a renthal i felt the difference there when i changed it

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