Austarion

Stumbled on this and it might be helpfull for those changing wheel/tyre sizes.
http://www.1010tires.com/tiresizecalcul ... ion=submit

Been using this for years, a really great tool.

Their offset calculator (as posted in the wheel offset guide: http://forums.austarion.com/viewtopic.p ... 10&start=0, thx to Tomsun) is also a nice simple tool.

To add something extra here I also find this tool useful: http://www.rimsntires.com/specs.jsp
Pity it doesn't allow stretched tyre combinations but still handy, particularly with offset and backspace conversions

No excuse for sad wheel fitment these days really. :)