You hit the nail on the head - someone emailed me with a 3 speed freewheel, an Atom, and that seems perfect - the gears are exactly what an old fart needs - a 19 for cruising, a 21 for hills, plus a 16 for those rare occasions I feel spry.
Not sure what you mean about interchangability - how can a spined and a threaded cog be interchanged? The clubman has threads on it for the cog - I had never seen one like that on any of the other 12 3 speeds I have.
Also - that two cogs on at the same time - that looks pretty ballsy! Does that really work!?!? I'd love to try that, however I have to stick with 1/8 chain to preserve the front chain wheel.
Thanks for the ideas - I've only just joined this list, and it's already paying off with a fount of info!
Mark
http://www.sciencemonster.net/
Date: Sun, 02 Sep 2007 21:33:37 -0500 From: Mark Stonich <bikesmith@earthlink.net> To: mark assaf <mark@sciencemonster.net> Cc: classicrendezvous@bikelist.org Subject: Re: [CR]WTB 50's Style 3 Gear Cog
At 9/2/2007 04:25 PM -0700, mark assaf wrote: > >Hello, > > > >I am making a slow, painful transition from 3-speeds to road bikes, > >and currently am driving an old Clubman with a 3 speed hub. I would > >like to keep the functionality the 3 speed provides, but add some > >lower gears. Does anyone have or know of where I could get, a 3-gear > >cog so I could add a derailer? These used to be made by, among > >others, Cyclo or Benelux.
Mark. Actually it was one company, Cyclo Benelux. The one I have been hanging onto is finally going to be used next week as I'm finally getting my '58 RRA together. And like you, I need a wider range. But they do show up on ebay. There may be one at the ABCE Swap meet in two weeks. Email me off list and let me know how high you are willing to go and if there is one at or under that price I'll grab it for you.
> >I could either use a three-splined cog or a regular threaded cog,
I've never heard of a threaded three cog converter, though the may have been made. Would have made sense IMHO.
> > as I have hubs for both. Threaded is preferred so I could keep the > > Clubman as original as possible.
You probably already know this but threaded and 3 spline drivers are interchangeable and it only takes a few minutes.
You have a couple of other options, till you find what you are looking for.
I've run 2 SA cogs back to back on splined drivers by eliminating the spacers. I ran 19-22 to split the ratios of an AW but 22-16 would extend the range of an AM or AC. Thanks to nearly flush rivets and thin sideplates, modern SRAM 1/8" chain is narrower than derailleur chain from 20-30 years ago.
You can also modify a 7 speed cassette cog to fit the splined
driver, and use it with a 1mm freewheel/fixed cup spacer and a dished
3 speed cog. http://bikesmithdesign.com/
I sold a 12t threaded cog to a British Moulton owner who liked to run 12-24 on a threaded driver with an S5 5 speed. (10 speeds the hard way.) Danged if I know where he found threaded 24s. (I just went down into my shop and checked how this would work, and neither cog could have many threads of engagement. Probably don't need many with a 12t.)
Look for an old 3 speed freewheel and gum up the works so it doesn't freewheel.
Some of the older 5 speed freewheels get pretty narrow if you remove the outer cog (or two?)
Mark Stonich; BikeSmith Design & Fabrication 5349 Elliot Ave S. - Minneapolis. MN 55417 Ph. (612) 824-2372 http://bikesmithdesign.com http://mnhpva.org
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