Originally Posted by
FastJake
Does this matter, at all? I don't run 10-speed but I mix all sorts of other stuff. I do have 8 speed chain on a 10 speed crank and that works fine.
As long as the speeds of the chain/cassette/shifter match isn't that good enough?
It matters when you are giving advise based on info given remotely, A lot of components will work together out of their design parameters, but if you want to try this, your on your own. In your case an 8 speed chain on a 10 speed crank may work, personally I wouldn't, and wouldn't suggest it to anyone else.
Shimano give their compatibility charts for a reason; to give optimum performance from their products, if you like to take the risk of getting sun-optimal performance, go for it.