Having built a few friction bikes I agree. Wind can be a big problem too. I'm talking about "wind" on the internet. Maybe should be called "fiction bikes" instead of friction.I would take those numbers with a grain of salt, especially with 33cc's.
That was exactly my situation with the weed wacker engines. Same everything right down to my fat but. I got about 20-22 mph level both directions via GPS. My first ever was a 43cc (Dimension Edge). Significantly faster but really crummy rack mount which is what forced me to "roll" my own. Roller pressure is critical.dang.
what should i expect to get for a 33cc with a 1 1/8th inch roller, 26 inch bike, 200 pounds then?
thx al