Re: [CR]WTB Sturmey Archer hub, more than you probably want to know.

(Example: Component Manufacturers)

Date: Tue, 21 Feb 2006 14:35:48 -0600
To: Sheldon Brown <CaptBike@sheldonbrown.com>
From: "Mark Stonich" <mark@bikesmithdesign.com>
Subject: Re: [CR]WTB Sturmey Archer hub, more than you probably want to know.
In-Reply-To: <p0623090fc020fc6c9134@[10.0.1.39]>
References: <43FA490D.7090607@pacbell.net> <6.2.3.4.0.20060221084442.04be0b88@pop.earthlink.net>
cc: CLASSIC RENDEZVOUS <classicrendezvous@bikelist.org>
cc: CLASSIC RENDEZVOUS

At 2/21/2006 12:32 PM -0500, Sheldon Brown wrote:
>Those are good, but we actually sell a lot more of the SRAM 24 tooth
>sprockets, which also work for both types of chains.

Those are nice, but most of my friends don't want to go that large. I use some homebrewed 24s and 26s
>I've toyed with the idea of making a close/medium ratio 3-speed from
>an S5 or FW by removing some of the internal parts. I suspect this
>could improve the efficiency, if one didn't need the range.

Should work, I've read of someone turning one into an ultra wide ration 3 speed for use with multiple cogs.
>>You can put the guts of any pre April 1984 5 speed into any pre
>>April 1984 AW or FW shell.
>What happened in '84? All of my Sturmey-Archer hacking has been
>with older models.

Darned if I know, but I've read it in a few places. Like you, I've hacked the old stuff.
>By the way, almost all of the parts of an S5 are interchangeable
>with FW. I used to regularly convert FWs into S5s.

Me too, but now I think functioning FWs may be rare enough that they should be kept for vintage bikes.
>You REALLY don't want to use an SA shifter on the left.

You don't, and I don't, but I've a friend who has 2 SA shifters on all 8 of his 5 speed equipped bikes. His are all S5/2s, or have /2 axle assemblies, so that might be the difference.

I've never used 2 SA shifters with the bellcranks. What sort of problem would I encounter?

Both of my wife's 5 speed bikes have S5/2s and she much prefers the SA shifter for the left. I intend to convert hers to S5 spec. I'm curious to see if the spring on the bellcrank will allow her to keep her shifters.
>It is my impression that S5s generally have less internal friction.

I agree. Fortunately I have a friend who hates the bellcranks, so we've swapped 3 sets of axle assemblies.
>The key to this is to only shift the left side
>_while_pedaling_forwards_. They work quite smoothly if you do this.

I still seem to have the occasional problem. The spring is also the easiest way to mate the Sturmey adjustment rod to the Shimano bellcrank.
>One used to be able to buy cable anchorages with a built-in spring.
>These were great for this application, also for using as a
>"pre-selector" for the right side cable.

That's where I got the idea.
>I don't believe that's correct. Springs don't "lose pressure"
>unless they are extended/compressed past the yield point.

You're probably right. But I've had shifting problems that I traced back to weak clutch springs.
>>FW
>>The problem with the FW 4 speeds is that it takes quite a bit of
>>cable tension to engage low gear against the extra springs, which
>>can sometimes overpower a worn shifter. Another is that the
>>indicator rods are rare and delicate. Also shifters are harder to find.
>
>Those are some of the main reasons for upgrading them to 5-speed.

That's why I did it, but now I have a small stash of shifters and rods.
>I have a bunch of technical/historical material on my Web site about
>older British bikes. See:
> http://sheldonbrown.com/english-3.html
> http://retroraleighs.com
> http://sheldonbrown.com/sturmey-archer.html
> http://sheldonbrown.com/raleigh.html
> http://sheldonbrown.com/raleigh26.html
> http://sheldonbrown.com/sa50.html
> http://sheldonbrown.com/harris/three.html
> http://sheldonbrown.com/harris/sturmey.html
> http://sheldonbrown.com/sa-1935-8.html

Thanks, I hadn't seen some of those.

Mark Stonich;
Minneapolis Minnesota
http://mnhpva.org
http://bikesmithdesign.com