Yeah, I thought about side walls and was looking at them and I do believe they will be too soft. I do have a huge section of a very large conveyor belt and it is a lot harder then a tire carcass. But it is thinner then my pads already.I'd love to buy some if CE has made them yet. No one sells round ones but boygofast and i dont do paypal. Fairacing, i made mine from tire sidewall but the rubber is too soft. I picked clumps out of the gears inside after 30 miles but i does work, doubt if it lasts long unless i wear down to a better surface.
I will be very proud if I can find something in my junk to work.