Optimimum tyre width for 7/8" roller

A mountain bike wheel can take anything from 1.25" to 3" tyres.

How critical is the tyre width for the roller?

What is the optimum tyre width for a 7/8" roller for use in a very hilly area?

My friction roller is 1 1/4in wide and you would need a tire centered on the roller with at least that width to get maximum traction. If you have a steel drive roller like in the BMP friction kit the wider the tire the more traction youll get. It just depends on the tire you want to run. I run a 2.125 semi slick on the rear and am very satisfied with its performance......rear is also beefed up with a nomore flats liner and a thorn resistant tube with 65lbs of air in it. The stiffness helps with the friction rollers traction.

I too live in a very hilly area. I have a Stanton fricition drive with a R/S 35 4 stroke engine and a 1" roller. I have spent a bunch of money trying to get the best setup.

The tires that came on my Landmark Crusier were 2.125", had a pretty agressive road tread, but were limited to 40 psi max. These were a disaser. Did fine on what few flats we have around here but it was just to "soft" and wore the tread pretty bad in 25 miles of riding.

I purchased a set of 1.95" semi slicks rated at 65 psi and it rides like a new bicycle. The higher pressure made this steel bike so much easier to ride. I now have 150 miles on the bike and it looks like it will last a long time. So 1.95" works fine for me.

I have since purchased a set of 2.125" semi-slick tires from Amazon (Niagra Bicycle Shop). These things are fat, wide, and square. I think they will probably work well but I'm not going to install them until the other tire wears out which may be a long time with my limited riding.

Could you tell me the top speed with your 7/8" roller? I have considered going to a smaller roller but my top speed with the 1" is about 21-22 mph and I don't want to go much slower than that.

I learned something this week which should have been obvious to me. You have to keep the engine at about 2/3 to 3/4 of maximum rpms when pulling a hill. That is the range where the maximum torque is. I was getting up speed for the hills then shifting down to 3rd gear and when the hill slowed the bike enough I started to pedal. By then the rpms were low and the motor was no assistance at all. It is acutally a drag. Now I hit the bottom of the hill at max speed in seventh gear and downshift as required to keep my cadence and keep the rpms up on the motor. This works so much better.

Hope this helps with you question.

I can verify that. Wide tires, and later, ones with no tread made a HUGE difference on my old Edge. Specially on wet roads.