Sturmey Archer hubs and chains?
 

I am interested in putting a Sturmey Archer 3 speed SW (1958) hub on my bike and I'm having trouble with the compatibility between the chain and the cog on the hub. The teeth on the cog are a touch too far apart to mesh well with the chain.

Not sure what the chain is, but it works fine with the Williams c34 style chainrings on the front of the bike, and worked well with the Shimano 5 speed freewheel that used to be on the back.

Is there a difference between the chains used for Sturmey Archer hubs and those used with other gear systems? If so, do chainrings compatible with the Williams c34 come in the same pitch?

Hope someone knows what I'm dealing with here. I've taken the hub apart, and aside from being a bit dry, the parts all seem in good shape. I'm looking forward to giving it a go on this bike!

Thanks,
Neil

Your probialy trying to use a 3/32 chain with the 1/8 cog. You'll need a 1/8 chain.

You know, I think you're right! Thanks.

Do you know if the 1/8" chain will work will work with the narrow chainring, or will I be able to find a new narrower Sturmey Archer cog?

Cheers,
Neil

An 1/8" chain will work on a 3/32" chainring. I am not aware of narrower S/A cogs. There is always the possibilty of a modified shimano cassette cog. But it's easier just to buy a BMX chain.

if your hub uses the common three spline driver rather than the older threaded driver, you should be able to find 3/32" cogs.. sturmey-archer still makes them and they are available from harriscyclery.com

If the teeth on the cog appear to far apart, then it's not a 1/8th or 3/32nds thing, because that's chain width. If the teeth on the cog were too close together, I'd diagnose chain stretch, but that's not the case either. I suspect aliens.

I initially suspected the pitch of the teeth differed between the chainring and the cog, but this was a faulty premise. In reality, the chain is not wide enough to seat properly on the cog, just as roughrider initially suggested.

However, this aliens thing may have merit too....

hmm.

Thanks to all for your words of advice.

1/8" width chain will run fine on narrower rings. SRAM, Shimano and IKT all make cogs to fit the SA hub and work with 3/32" chain. Newer SunRace/Sturmey Archer ones will too.

I sold 25 22T Shimano and IKT cogs last year, to people gearing down their 3, 4 and 5 speed SAs. Shimano are bright chrome and the IKTs are a darker finish like the older SAs

For those who need really low gears:
SA makes a 25t to fit the 8 speed hubs. The 8 speeds have a 63mm driver so the cogs can't be directly mounted on an older hub.

Yesterday I made a fixture to accurately center an older 18t SA cog in relation to a new SA 25t, for the purpose of TIG welding them together. The result turned out so nice, that I ordered several 25s today. I'll be selling them, but till I'm in production mode I won't know what to charge.

http://bikesmithdesign.com/SA/25t.jpg

PS. Good luck with that SW. The SW (Seldom Works) was introduced in 1954 as a cheaper, lighter replacement for the AW (Always Works). Big mistake, they re-introduced the AW in 1958.

http://my.ohio.voyager.net/~bdhayes/sa/sw.htm is a site that explains quite a bit about the problems. I may have a source of SW pawls. I'd recommend replacing them yearly.

You need to replace the chainring and chain. If I am to understand, this bike used to have derailler gears? The chain for this type of gearing is too narrow to work. You will also have to swap out the chainring because the chain won't work on your existing one. Simple swap.

thebikeguy, he doesn't need to replace the chainring. Simply replacing the chain is enough. A wider chain runs fine on a narrower ring.

My gut is telling me you need to remove the valve stem caps, roll the old bike to the tip, put a new bike in its place and install the previously removed valve stem caps. :D

I think I'll start with a new chain and go from there, stopping when things work. The bike probably originally had the SA three speed, and sometime in the early 60s was upgraded to a Shimano 10sp derailleur system, so it now has a double chainring up front. I am taking it back to basics......

Except for the super bad ass valve stem covers I have.:eek:

I suspect aliens.[/QUOTE]
if it aint the aliens its those damn gremlins