Helping a mate set up a second hand bike he’s bought, a Cannondale Bad Boy (2011?) with fatty rigid fork and disc brakes. It’s fitted with the original Cannondale 700c wheels and 700x28c road tyres. He says he wants to buy a second set of wheels and tyres for more off road use with some volume in the tyres to add some ride cushioning if possible.

It looks like the tyre clearance in the rear frame will ultimately limit max tyre width/volume. Looking at various options: another 700c wheel that takes larger volume CX tyre; a 27.5″ MTB wheel with a chunky tyre (within frame limits); and a 29″ MTB wheel and lMTB tyre.

Recommendations welcome, particularly from anyone with experience of the Cannondale Bad Boy and what would work.

Re cost, he’s working at the budget end of the price spectrum.

Any Cannondale Bad Boy owners out there?

See no reason you couldn’t fit CX tyres to the original rims, I’ve not measured them but I’m guessing they’re around 17mm internal.

Not had mine for long so not had a chance to experiment, but thinking 27.5″/29″ might work well off road, appears to be plenty of clearance around fork.

I have a bad boy 8 ultra but I won’t be much help. When I bought it the shop owner said he had one that he ran road sized wheels and also a set of 26″ mtb wheels but I don’t know what tyre. I know there isn’t much room in the rear in contrast to the forks which I reckon could take a fat bike tyre.