I have a buddy that just bought an F2. The guy he bought it from did afew mods (exhaust, sprocket) and also said he tried to mess with the air/fuel... unsuccessfully. I rode it yesterday and it reminded me of a diesel truck. It still had power, and I could tell it was geared to take off fast with the sprocket, but the engine definitely doesn't run smooth like my f4.

I've never used a jet kit, but is that how the previous owner messed with the air/fuel? Is it something we could adjust back? If so, does anybody have a link to any info on how to do that.

 

I would say talk to the guy you bought it from again and ask hiim exactly what he meant when he said "messed with the air/fuel" Then go from there.
Elisha

 

Carbs need cleaning, tune-up, spark plugs, bad gas, out of sync carbs...many things that can effect the running condition...[:@]
RB