Rosco NQ,
Spoke to the owner and did a few measurements..
Next time he said he would put the back roller about 8" higher as this give the bike more stability and support,as its tied down now when started.(probably should tie it down anyway)
The diameter of the rollers are 5" approx X 9" long,bought from industrial conveyors/boat parts or any kind of roller place.
One starter motor is a 12v out of a 350 Fee and the other a 6 cylinder ford.
bit of extra info=there is also a Bultaco kickstart gear roller to start one of these motor.
The material on the rollers can be bought from the local skate board shop which is used for the decks of the skate board (ask any kid
).
One more thing watch all feet hands and bits when starting this piece of machine as it bites
Hope I explained it ok...let me know if you need more info etc.
cheers Alison