gearing for folding bicycle

On Thu, 21 Jul 2005 03:19:18 -0500 A Muzi wrote:

Phil Van
Valkenburg built a mid-50s Peugeot like that with a Sturmey
S-5 and a TA triple for just way too many gears.

In 1968, when I first got to Madison, before there was a Yellow Jersey
and before Phil got into cycling, there was a bike frequently parked
on University Ave, with:

S-A five speed internal gear hub
5 speed "freewheel" (presumably locked)
Triple chainring

Seemed WAY cool at the time, but Andy is right that it was also WAY
too many gears.

-
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Jim Adney
Madison, WI 53711 USA
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On 21 Jul 2005 07:50:40 -0700 wrote:

I knew about the first and third ideas above, but I know nothing about
a Sturmey-Archer threaded driver. (I haven't done a lot with S-A hubs,
especially in recent years.) Is - or was - that something that's easy
to get?

Early S-A drivers and cogs were threaded. Late ones have 3 lugs. I
think Bendix introduced splined cogs and drivers.

It's probably no accident that the early threaded drivers used the
same thread as a freewheel.

-
-----------------------------------------------
Jim Adney
Madison, WI 53711 USA
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A Muzi wrote:
Raleigh used to sell a Cyclo kit with 2 or 3 cogs together
that snapped right on an SA splined driver. Raleigh dealers
offered new Raleigh 3 speeds with a six or nine speed
option and cheaply too. Under $10 IIRC. The impossibly
small box held your cogs, a new snapring, a couple of chain
links and a Cyclo flat-spring derailleur with a pretty
aluminum downtube lever. Full gear casing and aluminum
(pre-zip ties!) cable strips. That's the low-normal
derailleur Sheldon waxes nostalgic about occasionally.

A Sturmey Archer threaded driver can take any freewheel if
you block the body,either by jamming ratchets or
welding/brazing the inner and outer bodies. Phil Van
Valkenburg built a mid-50s Peugeot like that with a Sturmey
S-5 and a TA triple for just way too many gears.

More simply, removing the spacers on a regular AW leaves
room for two cogs with bevels facing away from each other
(Sizes 15 and smaller are flat, not beveled). Bill Putnam
discovered that Shimano cassette cogs also fit nicely with
all but 3 splines removed.

wrote:
I knew about the first and third ideas above, but I know nothing about
a Sturmey-Archer threaded driver. (I haven't done a lot with S-A hubs,
especially in recent years.) Is - or was - that something that's easy
to get?

Found on very old hubs
I don't recall the change year but at least fifties maybe
earlier.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

Lee wrote:
I'm building up a folding bicycle, probably a Swift Folder, and I'm trying
to decide on gearing. Most of the use for this bike will be light touring
(10-20 miles) while I'm traveling. I don't expect much in the way of
terrain, mostly flat areas.

So I'm trying to decide between setting it up as a single speed or fixed
gear, or with standard gearing. If I do the latter, I'm thinking that
non-indexing is the way to go. Easier to set up, less fuss when I get to my
destination.

The last option is an internally geared hub, but they are pricey...

Anyone have thoughts on this?

Thanks,

Lee



It depends on how you ride, your condition, and your terrain. I rode
around Boston and New York on a fixed gear bike with 27 inch wheels, and
it was OK. Most of the hills there aren't so bad. I was already fairly
good at hill climbing, and the fixed gear helped to teach me to be
better. I was using a low-ish gear, though, 66 inches (207 inch rollout).

It might be less fun on a small-wheel bike, since the small wheels suck
more energy from you.

I wasn't happy with Sturmey Archer hubs because the gearing was too
wide. Newer internally geared hubs may have fixed that problem. As I
remember, which could be wrong, the middle gear was direct (i.e.
whatever your chainwheel/sprocket provided), low gear was 25% lower than
middle, and high gear was 33% higher than middle. Compare that with
three adjacent gears on your freewheel, and you may see how wide that
really is.

But as you point out, either of these setups will simplify maintenance
quite a bit.

--
Tom Reingold
Noo Joizy

"Tom Reingold" wrote in message
...
Lee wrote:
I'm building up a folding bicycle, probably a Swift Folder, and I'm
trying to decide on gearing. Most of the use for this bike will be light
touring (10-20 miles) while I'm traveling. I don't expect much in the way
of terrain, mostly flat areas.



It depends on how you ride, your condition, and your terrain. I rode
around Boston and New York on a fixed gear bike with 27 inch wheels, and
it was OK. Most of the hills there aren't so bad. I was already fairly
good at hill climbing, and the fixed gear helped to teach me to be better.
I was using a low-ish gear, though, 66 inches (207 inch rollout).

It might be less fun on a small-wheel bike, since the small wheels suck
more energy from you.

I wasn't happy with Sturmey Archer hubs because the gearing was too wide.
Newer internally geared hubs may have fixed that problem. As I remember,
which could be wrong, the middle gear was direct (i.e. whatever your
chainwheel/sprocket provided), low gear was 25% lower than middle, and
high gear was 33% higher than middle. Compare that with three adjacent
gears on your freewheel, and you may see how wide that really is.

But as you point out, either of these setups will simplify maintenance
quite a bit.


Thanks Tom. I just picked up a pair of Spin composite 20" wheels, rear flip
flop. I'll see how the bike works as a single/fixxie. I'm also starting to
look around for a pair of hubs to build a set of 6-8 speed wheels...we'll
see...

Lee

Frank Krygowski reminisced:

Long, long ago I came across a guy riding a touring bike with a very
odd looking rear hub. I asked about it. Turns out it was a
Sturmey-Archer 3 speed with a five speed freewheel grafted onto it.
IIRC, he had 45 gears. Not very necessary on a 700C wheel, IMO, but
the 3 x 5 could be useful for a folder.

I had a similar rig on the Moulton Deluxe (16 inch wheels) I rode from
Boston to Montreal in 1969, I think that was a 4 speed freehwel on a 3
speed hub with a 72/52 double chainring. A friend used to note that
this was the only bike he ever saw with a 52 tooth granny gear...

I believe the freewheel was 15-24.

Anybody know if the adapting hardware is still available? ISTM it
wouldn't take much.

Andy Muzi wrote:

Raleigh used to sell a Cyclo kit with 2 or 3 cogs together that snapped
right on an SA splined driver.

Yep, I put one of these on my Elswick Tour Anglais back in '59 or '60.
It was a three sprocket model, on a four speed FW hub. I was the first
kid on my block to have a 12 speed bike when most folks hadn't even hear
of 10 speeds.

Raleigh dealers offered new Raleigh 3
speeds with a six or nine speed option and cheaply too. Under $10 IIRC.
The impossibly small box held your cogs, a new snapring, a couple of
chain links and a Cyclo flat-spring derailleur with a pretty aluminum
downtube lever. Full gear casing and aluminum (pre-zip ties!) cable
strips. That's the low-normal derailleur Sheldon waxes nostalgic about
occasionally.

We've got a few of the Cyclo 2 and 3 sprocket units in stock from an old
bike shop's stock we bought out...

Unfortunately, the smallest sprokets for these are 16 tooth, not so
wonderful for small wheel bikes.

A Sturmey Archer threaded driver can take any freewheel if you block the
body,either by jamming ratchets or welding/brazing the inner and outer
bodies.

I've still got a couple of bikes set up this way, my 72 speed OTB:

http://sheldonbrown.org/otb.html

and a 54 speed setup on one of my home-made tandems.

http://sheldonbrown.org/bicycle.html#t3

There's no actual need to block the bodies. I did usually remove the
adjuster shims from the freewheels when I used to do this .

More simply, removing the spacers on a regular AW leaves room for two
cogs with bevels facing away from each other (Sizes 15 and smaller are
flat, not beveled).

I did that when I was in high school, back in the Pleistocene...

Bill Putnam discovered that Shimano cassette cogs
also fit nicely with all but 3 splines removed.

Yep. My Kid-Kid tandem uses that system:

http://sheldonbrown.org/bicycle.html#kkt

In the olden days a Sturmey trigger shifting a 2-cog derailleur predated
"index" systems!

The Sturmey-Archer hub was an early application of space technology to
consumer products: planetary gearing!

Sheldon "Too Many Gears" Brown
+-------------------------------------------+
| It's easier to be original and foolish |
| than original and wise. |
| --Gottfried Wilhelm Leibniz |
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Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
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