I had clutch slippage issues with my SSR Razkull
with piranha 140cc semi automatic with V2 head and cam
I then added
TBPARTS - H-D AUTO CLUTCH KIT 69T FOR PIRANHA YX140 SEMI-AUTO
TRC-1340
This clutch held the power without slipping
past sixty five miles an hour
Clutch works great, slippage issues cured