polymer chain

Harley's have used polymer toothed belts for years now. Trek makes at least one commuter bike which uses the same belt design, along with an internal geared hub. I've looked at the bike at my LBS and they are pretty cool for an urban bike. Have no idea how the life or cost of the belt compares to a standard chain set up, but one advantage for commuters is of course no messy chain lube to deal with.

Yeah, are you sure you're not talking about a belt drive? As dhk says they're nothing new.
Though they can be cleaner than a chain they aren't as efficient, they wear out faster and they can make a maddening whining noise at speed.

There are chains made from plastic, but they are generally limited to very light loads, such as for complicated toys.
There are also chains which have plastic rollers and steel side plates, used for conveyors.

To my mind a plastic side plate just wouldn't take tension very well without elongating and the rollers would deform (or crush) on very narrow sprockets. Both of these effects would tend to physically stretch the chain (quickly and perhaps permanently) which would make for poor meshing.

dhk2 said:

Harley's have used polymer toothed belts for years now. .

yes that`s what i meant