I just jet my quad after taking off the lid, i switched the main from 162 to 165, pilot from 42 to 45 and the needle clip went up a postion. it seems to run good, doesnt afterpop as much but every once in awhile when i rev it low to mid rpm and let go a little shroud of fire comes out of the exhaust what causes this?

 

im not sure but this would help cause when i was riding i ran out of gas and it was starting to stall so i shifted down fast to keep up my rpm's so i had time to switch to reserve and my friend behind me said i had flames comming out of my silencer. so it must not be getting enough fuel thats what i think

 

flames out of exhaust...

Rich fuel mixture to the point where too much if being dumped in and unburnt fuel is moving into the exhaust.

The fuel then ignites inside the exhaust and you get a flame.

 

Carmelo, On the YFZ is that 162 and 42 the stock jets that come with the bike and you just bumped them up to 165 and 45? That sounds a little big.

 

do you have the cover off the air box and are you seeing the flames while in neutral or while riding?

has the quad sufficiently warmed up?