[BadCarma505]

My wife has a 2008 CRF100 and when you twist the throttle really quick the engine dies. It makes no difference if the engine is cold or warm. Is this just a common symptom of a non accelerator pump carb? Are there any mods out there that anyone is doing to the carbs that improves performance?

Thanks

[Asmith]

Rejet will help, especially going up on the pilot jet.

[Billys2006CRF100F]

Factory jetting is slightly lean. Adjusting the fuel screw out may help a little but, it's not completely curable. If it's happening in neutral, than that's pretty typical. It shouldn't be a problem in gear riding.

[BadCarma505]

The fuel screw is not adjustable. This is the same with my son's '07 150F. is there a kit out there to replace the stock POS with an adjustable fuel screw? Or is this something which i will have to fabricate myself? There has got to be more CRF 150F & 100F owners out there with the same question. Anybody........?

[Billys2006CRF100F]

The 2005 and Up fuel screws ARE adjustable. You just need the right tool to do it. The fuel screw is a brass colored "D" shaped screw on the underside of the carb just forward of the float bowl in a recessed hole. The screw points straight up. If you call Dynojet directly you can purchase their fuel screw tool for only a few bucks. The part number is DT-008.