2009 YFZ 450r

[machinehead]

Just did top end , new piston, ring and wrist pin .
Valves not touched.
Motor cranks fine with spark plug out .
We have compression readings of 120 psi and 145 psi.
With spark plug installed , motor barely cranks .
Camshafts installed correctly lined up to TDC.
Auto decompression lever on exhaust cam appears to be functioning .
Any advice from the motor heads ?

Thanks .

 

[Mikehunt]

Maybe try posting here for more help Yamaha YFZ450 Forum : YFZ450, YFZ450R, YFZ450X Forums