Ok, so it's probably been asked before but I have a rear 17" that's just the right size for my front supermoto. Can I just get a 4.25" rear and lace the old rear rim to the front hub with the right spokes? I've heard both "no it's impossible" and "yeah sure".
Before I unlace my wheels and find out halfway no go, does anybody know?
Basically. I talked to a few rim builders who told me you can't. Sorry!
Check out the deal that East Coast Wheels has been running. Your hubs laced to Excel rims for $600, or $500 for the rims and spokes and you do it yourself! It was well woth it for me. And they are great people too. I had one problem with wheel alignment, but that's pretty typical from what I hear unless you give them your bike to lace up to.
If you have any other questions, please feel free to write. And good luck!