Papa Tom

For years I ran a bicycle recycling program that completely avoided multiple-speed bikes. These days, I've got a bunch of BMX-style chain rings around the garage and a bunch of neighbors knocking on my door asking me if I can help fix their kids' multi-speed mountain bikes.

Right now, I've got an XMart-type 18-speed MTB with both front chain rings badly bent. It's a single-piece crank, so if I only had the right chain ring, I could simply pop one on and, at least, make it a working 6-speed. Needless to say, all my chain rings are for single-speed BMX chains.

This is going to sound like a dumb layman's question, but can I get a single front chain ring (any size) for a 3/32" chain, or do I have to troll the neighborhood garbage to find a true replacement set of rings for this bike?

dsbrantjr

First, bent chain rings can often be straightened. Bent spiders can also be straightened: Straightening Chainwheels

Failing that, make sure that the chain rings are removable, many XMart-type bikes have them riveted to the spider. I suppose you could drill out the rivets but getting new bolts/nuts to fit correctly could be problematic. If you are able to remove them then you will need to find rings with the correct bolt circle diameter. Single chain rings are indeed available, the Web is your friend.

Bill Kapaun

You might check to see how a 5-8 speed chain "lays" on your chain ring. It just might.

Papa Tom

These are too far gone to be straightened. The person I'm fixing it for tried to remove pedals that had been installed in reverse (by K-Mart!) and ended up using a crowbar to hold the crank steady while he totally ripped the threads apart with a vice grip. The two chain rings were severely damaged in the process.

I am not using any of the original crankset, so I don't have to remove the rings. What I need is a BMX-style chainring with a center hole and an offset "locking hole" to keep it in place. The issue is, it's got to be one made for a smaller, multi-speed chain.

LesterOfPuppets

Some Walmart BMXers and cruisers do have 3/32" rings. Seems like most of the kids bikes do (18" or smaller wheel).

Cheapest aftermarket one I know of is at Niagara, has the opposite problem that the kids bikes do, it's a little big while kids bike rings are kinda small.

Inline OPC Chainwheel 44T x 3/32" Single Chrome

LesterOfPuppets

Ahh, here's a cheaper one with a much more palatable tooth count for running with 26" wheels.

Sunlite Chainring with Double Chain Guard, 36T

Papa Tom

Thank you. I went to my trusty LBS guy and he gave me a ring for scratch. I gave him five bucks anyway. Works great, but man, this Free Spirit bike is real crap. I almost want to buy the kid (my neighbor's son) a new bike just to keep him off this thing.

fietsbob

I like Surly's stainless steel chainrings , they are thin enough for more than 8 speed chains ..

but OK, off topic in a junque restoration project thread. ..