I hav an early model srx4 with a 3tb xt6e engine in, now here's the problem. The upper chain length brushes the inside of the frame. Very slighty, but i can hear it.
So my question is how much contact is acceptable? I cant feel any heat generation... I dont mind taking a chain life hit from the, slightly, misaligned spockets, just worried bout the catastrophic!

Why don't the sprockets line up ?

Can you get the wheel spacers modified to get everything to run true ?

I would rather my chain could "whip" about a bit without catching things, even a bit of contact must have some effect; especially when combined with some mud / wet sand / other debris.

Chain failures are funny things; sometimes the chain just rolls off the sprocket and drops on the road. Often though, it breaks and gets wrapped up in the rear wheel. Or gets around the front sprocket and smashes the engine casings.

BYT

The engine output sprocket is further to the left than on the original engine, if i shimed the rear spocket it'l bring the chain even closer to the frame.

Have you tried other sprockets? Maybe one for a SRX600?
Or could you have some material machined from your sprocked to make it set closer to the engine?

Steve