Esr 38 mm as carb all I can say is its great. Ordered it Friday around 3:00 was at my door today. Put it on fit very good easy install. Started it up adjusted the idle and air needle. Let her worm up and went for a ride. The power is the smoothest power I have ever had on a 2stroke. Throttle is crisp and smooth. Main is to rich but still preformed very well on top end. I would recommend this carb to anyone. Best $220 I have spent on it so far.just for reference carb is on a.
1987 250r
esr 310 non pv with trx9 port work race fuel dome
esr trx5 pipe
factory ignition
stock reed cage and boyson reeds
stock air box with k&n
carb bell on air filter side was machined down to fit factory air box
48 pilot 180 main dgh needle on 4th clip and as 2.5 out
