Originally Posted by BikePilot
FWIW I don't think 11:1 compression, even on a bore/stroke combo this large, is necessarily problematic so long as there is no detonation problem or engineering weaknesses. As an example, my old porsche 968 has a 3.0L 4cyl motor with 11:1 CR, 104mm bores and 88mm strokes. Mine has 150k miles on it now and runs just dandy. Rev range is also fairly close to that of the XR. (there are of course lots of other examples, street bikes, etc. as well).
I agree, if it still runs on pump gas, its probably not wound too tight.