I want to mount up bigger wheels

I mounted up a set of EX500 wheels on my race bike. I did it so I could use a 110 front tire up front and another 120 front tire in the back. EX500 wheels are 3" wide in the front and 3.5" wide in the rear. These are exactly the right widths for a 110 and a 120. Worked great. It took nearly 100 hours of measurements and calculations to figure out what to tell the machinist to do to the wheels and spacers to make it all fit (wheels centered etc.) Cost was about $800 before buying the tires

EX500 wheels won't bolt right up. You can use your stock axles, but that's about it. The spacers are wrong, the sprocket is in the wrong location. Both rotors are in the wrong location. The rotors are a different size, so the calipers are in the wrong location. I have drawings which show what needs to be machined, but the end cost is still exactly what I paid. Yes it's easier to do a second set, but the only part you'd get to skip are the measurements and calcluations and I didn't pay anything for that part since I did it myself. I paid $250 for a set of wheels including rotors (which I didn't need) and hardware: spacers, and cush drive (which I had machined down).

Anyone interested in going to 17" wheels is probably better off getting a set of 16" wheels welded up by Kosman (they are the ones that did the machining work on the EX500 wheels too).

Unless you're going to race it's not worth it. Even if you are going to race, it's still probably not worth it. :-)