Can anyome enlighten me on this one? Our Ram Stinger 100 is bored out to 53mm (45mm stroke), ported cylinder, worked head, now on 3rd piston change! It runs on a Dellorto 21mm phbg orginally jetted at 115 main jet, now on third piston gone down to a 107 and popped another 1!
Plug test always o.k until it pops then it looks lean but if you jet up it runs too rich God Knows on this one!
Did a compression test before last piston popped and pressures on 2 readings were 160 p.s.i and 165 p.s.i looking for a quick answer, is compression too high (we run with NO head gasket) or should I look towards the carburretor on primary jet?
Forgot to say exhaust is an FMF Fatty off a KTM 65 cut to fit and works great.
This has been built for hour and a half Enduros and completed everyone but pops a piston when my lad goes on a flat out track!
Any suggestions welcome but I can tell you how quick to change a piston!!
Plenty of power on tap but running out of pistons.Look forward to some interesting replies on this one Regards
Rod & Jak