In my HPI RS4 the front belt keeps wanting to veer to the left side of the differential pulley. Sometimes it'll ride up over the pulley's lip edge and cause binding and drag with the bulkhead interference.
I have just put in a new plastic pulley set because the old one was worn down on the left side and the belt kept going off. I tried to remedy this situation by putting more tension and changing the angle of the tensioner in a way that it steers it to the right side.
During roll out I verified this did work and I thought all was good and improved.
Now 5 gas tanks later I noticed I have completely destroyed the left side of the front pulley beyond even what the replacement had. Now during roll out the belt wants to ride to the left harder. I inspected the pulley and it looks like somehow it was able to make a ~3mm wide groove down past the teeth just right before the pulley's left edge all the way around (radially)! That and the left edge of the pulley has taken some wear as it's thinner and consequently more flimsy. I was running in a dusty parking lot doing WOT passes but I'm still puzzled how this happened this time around so quickly?
Can somebody help me with my belt problems? The way the plastic parts screw to the chassis (counter sunk screws) and the pulley shafts are an exact fit, I don't really see any possible potential for belt alignment or mis-alignment in my case?
What do you belt guys do?