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

(Example: Component Manufacturers:Ideale)

Date: Tue, 21 Feb 2006 10:43:22 -0600
To: Bob Freitas <freitas1@pacbell.net>
From: "Mark Stonich" <mark@bikesmithdesign.com>
In-Reply-To: <43FA490D.7090607@pacbell.net>
References: <43FA490D.7090607@pacbell.net>
cc: CLASSIC RENDEZVOUS <classicrendezvous@bikelist.org>
Subject: [CR]WTB Sturmey Archer hub, more than you probably want to know.

At 2/20/2006 02:56 PM -0800, Bob Freitas wrote:
> I wanted an alloy shell as I thought that might be the hot setup.

First off, you don't want any of the single cable 5 speeds, although SunRace/Sturmey Archer may have finally gotten them sorted.

Very late S5/2s were available in 36h Alloy Shell. I bought 2 NOS last year. The downside is a modern looking, somewhat heavier shell than the early ones. The upside is nice thick flanges. Early hub flanges were no thicker than the steel ones, sometimes failing and requiring several spoke washers when used with modern spokes.
>Now it seems like the gearing of these late hubs might present a
>high high high top gear (but I plan to use either Campy or TA cranks
>in a single chainring setup so I should have some flexibility in
>gear choice, though frame configuration probably will call out
>something closer to the 42t end of the spectrum VS the 52t)

We have 5 bikes with S5s or S5/2s (I've never even seen an S5/1) and 6 more hubs that will be installed on bikes as I find time. We gear them such that 90% of our riding is split evenly between 3rd and 4th. My brain knows there has to be more friction in 4th, but my legs can't feel it. Geared thusly, it doesn't take much of a downhill or tailwind to make 5th gear useful, and low will get me up any hill in town.

Shimao Nexus cogs work fine with 3/32" or 1/8" chain. I buy the 22s, 10 at a time for friends and family.
> So back to the original question ........................ I would
> like an appropriate SA hub which would allow me reasonable climbing
> gears plus some sort of downhill ability. I am not planning any
> TTs so close ratio hubs will not be practical but the TAYLOR
> probably was originally configured in that direction but I no longer am.

I always found the ratios of the AW 3 speed to be a bit too wide. I find the range and ratio jumps of the 5 speeds to be the perfect compromise.

You can put the guts of any pre April 1984 5 speed into any pre April 1984 AW or FW shell.

For shifters you can use an AW shifter on the right and another on the left, or better yet a friction bar end or thumb shifter.

Last year I bought 6 NOS 5 speed SAs off of Ebay. The easiest to find are the steel shelled S5s with 28h. I did use one with 28h on my wife's recumbent, with a super light Sun Chinook rim and butted spokes. Two of the other 28s went into 36h AW shells.

S5 or S5/2? S5s had a bellcrank and a pushrod. The early bellcranks were quite horrid things bent from sheet metal. Later ones are very nice indeed. I've seen later, NOS ones go for $40 on ebay, more than I've ever paid for a steel shelled NOS 5 speed hub. I'm set up to tap Shimano bellcranks to fit Sturmey axles, but the leverage is different, so you can't use them with an SA shifter on the left. http://bikesmithdesign.com/SA/bellcranks.jpg

The upside of the S5 is that the left cable is slack, and no springs are compressed when you are in medium ratio mode, which is most of the time.

The downside is that you pull the cable of mesh the square ended dogs when shifting to wide ratio mode. If the ends of the dogs butt against the other, the cable stops moving, and you are left in a false neutral. Careful shifting will eliminate this as a problem, but I'm not always careful. So I add a spring between the bellcrank and the threaded adjusting rod, as shown on the Shimano bellcrank in the photo. With the spring, the cable keeps moving if the dog ends butt against one another, and the shift is completed as soon as one moves.

S5/1 & S5/2 The upside is that since you pull the dogs out of engagement, instead of pushing them together, the shifting problem won't occur.

The downside is that there is a bit of extra drag, and spring that does engage the dogs is almost always compressed. So unless it's made from very good stuff, I expect it will eventually lose pressure.

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.

OTOH the 5 speeds use common parts. AW shifter, at least on the right. An AW indicator chain can be used on an S5/1 or 2, and you can make an S5 pushrod out of a nail. In fact I prefer the nail to the stock pushrod. The extra gear on top allows you to add a couple of teeth on the rear, for a bit of help on the hills.

Mark Stonich;

Minneapolis Minnesota
http://mnhpva.org
http://bikesmithdesign.com