If I remember correctly, and I may not (LOL), I believe there was a gas powered trike RC kit from kyosho. They are pretty uncommon, which means they can be costly. The gas powered atc90 trikes were meant to cruise by themselves, non RC, or you could hook a string up to them and let them go around in circles.
Nicholson 500x (Project)
Nicholson 185s
Nicholson 110 (That takes an atc70 tank)
Ascott 500 head/350x (Project)
Homebuilt Racer Chromoly Suspension 110 (Ragin Runt)
PK Racing Suspension 70
A+ Inc Suspension 70
AWS Aluminum 90 frame
Hi Performance ATC Suspension frame rd350
Hi Performance ATC Suspension frame 90