Anything's possible mate, the wheels are the same size as yours, but you'd probably need to make up wheel spacers, re-space the Yamaha brake discs, (if the discs are the same OD and thickness as yours, of course) etc.
Your axle sizes will probably be the same in dia, not length, from my limited experience. If you're buying the Yamaha wheels, make sure you buy everything to go with them (discs, axles, sprocket carriers, etc) as you'll probably have to "mix and match" the Yam and Honda parts to make it all work.
Finally, don't pay too much for them, they're an "aquired taste" (not everybody likes them) and most of those horrible old Yamaha triples are worthless, so the parts prices should be cheap. Cheers, Terry.
