I have just aquired a powerjet carb for a 2st 125. I understood how to jet my old low tech carb but have been a little thrown by the extra jet in the new carb. Consequently I am struggling to get it right in high end, full throttle situations.
My main jet is way leaner, by five jets on what would normally be on the edge, but still not dets on the counter. piston is fine.
comments anyone?
Did you ever notice that an engine pings worse under full throttle at lower RPM's?
The powerjet adds fuel at full throttle at lower RPM's when the engine needs a little extra fuel to pull the load. At high RPM's the powerjet shuts off, leaning the mixture when extra fuel is not needed. The extra fuel provided by the powejet makes up for the smaller main jet. In reverse, the system effectively leans the mixture at very high RPM's when you can get away with it without detonation. Lean mixtures make more heat which means more power but only as much as you can get aweay with without causing a siezure.
powerjet carb???
