hi i have a atc 70 that i just got back together after some low compression issues after i had just redone the motor on it with new piston and rings new high lift cam and new valves i put it back together the first time and had low compression and found out after taking it apart again the new exhaust valve i put in was not seating tight bad brand new bad valve pissed me off but any way to my question i have it back together and running it idles but when i trottle up fast it cuts out i can do it slow and it usually does fine do i have a jetting problem its got good compression now timings right valves clearance is right any help will be appreaciated