What are the worst friction drive problems you have had on the road?

There is lots of information on friction drive in the diy section. I have tried tire tread on metal rollers held on with everything they don't stay for me. I have tried sandpaper which seems to work best on low reving emotors. It ate up my tire when on a weed whacker. I used metal with a small tooth print it worked pretty good and didn't do too much damage.

I never tried the skateboard wheel on a weed eater but I did on electric and it seemed to do very well indeed. Right now on my E scooter motor friction drive I am usind sandpaper on metal roller.

I never had the flat tire thing going on. I did wear a few out and have them go flat but I didn't pick up an more stuff with a friction drive than I did with a china engine bike kit.

If you go with Jb weld and sand (which is easy) go to the craft store and buy some craft sand it is very fine and will not eat up the tires too badly. Play sand is course and will chew them up. I put on a thin layer of jbweld then sprinkle on sand then another thin layer of jb and sprinkle sand. I use three or four layers.

Pvc Pipe joins will not hold up to friction drive so don't waste your time on them experiment is all I can advise. Balance your drive as good as you can because I have shook plenty of engines apart.

worst problem ive had is the engine spitting in half (crankcase)

I am at the moment running a motor called a bumble bee it seems okay for now. I used my plumbing tube cutter to cut a roller from a seat post. It seems to work pretty well but I haven't used it a long time yet. I have some coaster tires on the way which should also help the roller.

What I am trying to talk myself out of building is a four cycle small greyhound from harbor freight.. I worked all the bugs out on the bumble bee but frankly it is running too well to mess with now and I hate to have two bikes around that are the same. In addition I have a really good e bike with lots of batteries I need to use as well. I have to get more time to ride the bikes. Once the weather turns I'll do that.