I plotting a home built sand/snow bike, not an alrounder like a true fat bike just an experiment in floatation cycling, already ordered some wheels and tyres. The wheels are 4" diameter lawnmower wheel rims shod with 3" cross section baloon tyres giving 10" total diameter. Thats stoopid you say and yes your probably right but I can in theory fit 3.5" high x 11" wide tyres to this rim which are still reasonably round profiled with a huge footprint. Will require bolting a very wide fork arrangement to an existing frame and elevating said frame plus lots of tortuous drive chain routing but all that looks fun. Dont expect any quick progress but do expect one ugly barsteward of a bike.
These are the cheapo wheelshttp://www.northerntooluk.com/tyres-and ... 3431E.html
and these are the tyres I might be able to fithttp://www.allterraintyres.co.uk/index. ... s_id=90414
I haven't done anything this stupid since I coverted a mixte framed road bike to a short wheelbased recumbent using bits of wood and a cut up old mtb frame. Was doing great untill the pedal boom snapped right in front of a bus shelter full of jeering laughing teenagers
Keep you posted