94 - 99 Monsters had axle sizes of 17mm-rear/20mm-front
00 - 01 Monsters had 17mm-rear/25mm-front, and I'm pretty sure the 900ss models made the same switch.
Mind you, wheel makers do all sorts of hubs/spacers so no reason you shouldn't be able to get hubs that fit regardless.
Someone posted a pretty extensive list on one of the wheel/axle/fork mod threads. IIRC, your info is correct but the switch may have happened in a different year for the SS.
Dannyboy, do a search for "25mm axle" or "wheel swap" and a few other key phrases. There's tons of thread about the subject. The gist of it is your older monster has a 20mm front axle and AFAIK, all the five-spoke wheels have 25mm ones. Check out my "Teaser, Scrambler almost finished thread" (you can find all my posts by clicking on my user name) I wrote pretty extensively about putting some 25mm axled wire wheels on my '99, but there are differences between those wheels and the 5-spoke wheels so all the info won't apply.
