Classic & Vintage - 1/8" vrs 3/32" chains and freewheels

OK, here is one I am ignorant on and would like some help from the knowledge guru's. What is the difference between 1/8" chain/sprocket setups a and 3/32"? I presume one is narrower than the other, does that mean they can not be mixed? Can you mix one way and not the other? I am currently looking at a freewheel that is marked as for 1/8", which is why the questions. Thanks for any enlightenment you guys can supply!

A 3/32" chain cannot be run on 1/8" freewheel or rings. A 1/8" chain will work on a 3/32" freewheel and rings, but it will be sloppy and wear the gears quicker. I would recommend matching things correctly. 3/32" is generally for the road and 1/8" is genearlly used for track (and bmx).

Hmmm. I have several bikes with 1/8 rear cogs and 1/8 chain, but 3/32 chainring. I have never noticed any sort of slop. I also rather doubt that there is any appreciable difference in wear rate.

Fixed people have been mixing this way for a long time. Really does not seem like an issue at all. I suppose I would not go out of my way to set one up this way. (Why add a heavier chain if it is not needed?) But if you happen to have a mix of parts that you otherwise like, I would not hesitate one bit.

jim

Hmmm. I have several bikes with 1/8 rear cogs and 1/8 chain, but 3/32 chainring. I have never noticed any sort of slop. I also rather doubt that there is any appreciable difference in wear rate.

My information is from what I read from somewhere - not too reliable - I have no experience with a 1/8" chain on a 3/32" chainring. I would go with your experience over my information.

1/8" freewheels were from a time when common was also a fixed cog waiting on the other side of the hub to be switched to. a 3/32" chain will not work as stated, also, a 1/8" chain on a 3/32" freewheel will not work for the vast majority of freewheels, as the cogs are too close, unless is is a very wide range freewheel where the chain can offset into free space, closer ratios will have interference. Long ago we had a customer who almost made it work except for the 14/16 cogs, he added washers and longer fasteners to the jockey wheel cage too, resourceful, and would have saved the cost of a second (and third correct) chain and time if he came to us first.

Hmmm. I have several bikes with 1/8 rear cogs and 1/8 chain, but 3/32 chainring. I have never noticed any sort of slop. I also rather doubt that there is any appreciable difference in wear rate.
jim

I have found the issue to be in the other direction: running a 3/32 chain with 1/8 cogs. It's too narrow and is bound to cause trouble.

Neal

The only multispeed 1/8" cogsets I have seen were hybrid drive train adaptors for Sturmey Archer 3-speed epicyclic hubs, to give one 9 or 12 speeds. I used those with 1/8" chains and either 1/8" or 3/32" chainrings, which worked fine, as long as I had enough width in the rear derailleur cage. (Old Campagnolo Gran Sports, Cyclos, and Simplex TdFs worked fine.)

The only multispeed 1/8" cogsets I have seen were hybrid drive train adaptors for Sturmey Archer 3-speed epicyclic hubs, to give one 9 or 12 speeds. I used those with 1/8" chains and either 1/8" or 3/32" chainrings, which worked fine, as long as I had enough width in the rear derailleur cage. (Old Campagnolo Gran Sports, Cyclos, and Simplex TdFs worked fine.)

I have a four-speed block on my 1961 Raleigh Lenton Grand Prix, and it uses a 1/8" chain. But anything produced after the mid 60s would use a 3/32 chain, I'd imagine.

Neal

I have found the issue to be in the other direction: running a 3/32 chain with 1/8 cogs. It's too narrow and is bound to cause trouble.

Neal

This will not merely cause trouble, it simply will not work. At all. For even a second.

ko,

I have a four-speed block on my 1961 Raleigh Lenton Grand Prix, and it uses a 1/8" chain. But anything produced after the mid 60s would use a 3/32 chain, I'd imagine.

Neal

That's probably one of the very last 1/8" multicog freewheels. My 1962 Bianchi had a 5-speed Regina freewheel and a 3/32" Regina chain. Both Capos (1959 and 1960) came with 3/32" chains and cogsets, as well.

Actually the unit I was looking at acquiring is an old Cyclo 4 sp, which would agree with what nlerner has.

1/8" chains don't flex as well as 3/32". If you want to run a bunch of gears with a quiet drivetrain and not get flaky shifting, go with 3/32"