Sorry been meaning to get back on this thread for a few days.
Sorry its not truly a "big wheel," my inspiration for the title was like a big wheel KX85... stock those are 17/14 but they did make them in a 19/16 at times. I do dig the big wheel (fat tire) bikes but never seem to find one cheap. I had a Suzuki RV90 for a minute but sold it off in an effort to focus more on my yamahas - plus the motor on those seemed more odd ball to get parts for.
Born, I appreciate the offer on the shocks. 16" is probably too tall but Ill keep it in mind.
Graham, your DT100 came out nice. Too bad your missing the cover tho. These bikes are cheap to repair motor / suspension pieces but plastics are scarce and pricey. That rear fender is an odd ball and pricey to find. I believe the set on my bike is the only tank covers i have or else id send you some. I do however have like 2.5 of these bikes in pieces so i have other misc bits if your looking for something. You could also consider just getting the older MX/DT 100 gas tank and putting that on there.
A few years back my buddy bought a ragged out 80' Yamaha DT100 from AMA for like $200. It ran and we beat it on the trail for years. That stupid bike to this day still runs. Im very impressed by these motors... nothing to race on but snappy enough to have fun with.
Potr zebie, I have a street legal GT80 that is very snappy. Ive determined Yamaha is my favorite enduro / trail bikes... they are cheap, plentiful, and actually pretty peppy generally. I thinned out my fleet of bikes to focus on my QT50's, GT80's, and RT/DT100's.