My son has a 2004 Predator 90. Over winter we installed a performance CDI, a Super Coil, a Hetrick Power Up Kit that included the exhaust system, a clutch kit (1500rpm torsion spring, 4.5g roller weights, and black clutch springs), and a different main jet. I also drilled out the clutch shoes at the same time. It has been running great ever since.

Now last week, it began acting up. When he takes off at the line (drag racing), it seems to rev up fine, but it just rolls off the starting line. Once he gets out about 75 - 100 feet, then it takes off awesome. Not sure if the belt is slipping or what is going on. I took the clutch apart on Saturday, couldn't find anything that looked out-of-whack, put it back together, and it ran great. My son raced with it on Sunday and it was doing it again. Belt looks great!!

I have a few leads from talking with some friends.... I was told that it may be a cracked reed or the torsion spring may need replaced. Does anyone have any idea what may be going on here?

Thanx.