Mix & Match...

[SirJoey]

I'm already well aware of the difference in chain & sprocket size between single speed & multi-speed bikes. What I'm wondering is, could a guy get by with using a multi-speed chain & front derailleur with a coaster brake rear hub?

This may be a dumb question, but it seems to me, the coaster brake sprocket would eventually "wear in" to match the chain, since it's a small sprocket. Has anyone tried this, or is it just totally out of the question? :confused:

[Richie Rich]

It should work, Joey, as long as the chain pitch is about the same for the coaster. You'll have to remove the rear derailleur or you won't be able to stop. And you'll have to decide which sprocket to use for the pedals since you won't be able to change gears with a fixed chain length.

Give it a try and let us know....

....Richie >>

[SirJoey]

Thanx Richie,

You've just rendered the matter academic. I hadn't planned on having a rear der, but I overlooked the obvious point you made about chain length changing when shifting the front one...

I was wanting to be able to shift the front chainrings, with a coaster brake on the rear, for my (currently single-speed) Trixter trike. It would've been nice... :(

[TheKid]

I did this with a 3 speed internal gear hub. You need 1/8" x 1/2" chain for the coaster brake sprocket. 1/8" chain will work with the thinner front chainrings as well as the thicker rear sprocket, but the 3/32" chain we use for derailler systems is too narrow for the coaster brake. You'll also need a spring loaded chain tensioner to keep the chain at the proper tension when changing the front gears. A erailler won't work for this, because it's designed for the narrower multi speed chain, unless of course, you find a way to modify it to take the 1/8" single speed chain. I also found that cutting off the brake lever on the hub and installing a hand brake for the rear is highly recommended.
When I install the 8 speed Nexus hub on the tadpole, I'll be using the rear derailler as a chain tensioner, because the sprocet is for 3/32" chain.

[SirJoey]

Can't install a handbrake, due to the brace (boom) tube. This is basically a SpinCycle we're talking about here. Thus, the reason I wanted to retain the coaster brake, but still be able to shift across 2 or 3 chainrings on the front...

It occurred to me to add the chain tensioner, after Richie's observation of varying chain length, that I'd overlooked, but then it's getting into too much hassle. More than I'm willing to put into it, anyway.

Good info on which chains will work with which systems, though! So the day's not a total loss after all, cuz I learned something! :D