Raleigh Twenty wheel rebuild

My partner's Twenty was in a bit of a sad state, just riding it along you could feel the whole bike just wobble from side to side like it was a broken washing machine.  The rear wheel had about 3 or four broken spokes and the rest were just waiting to break.  So I decided to rebuild it and strip the hub and give it a good clean.  The wheel was completely original and was dated back to 1975 which means it gave 36 years of service which isn't anything to sneeze at.

Covered in decades of leaked out oil and grease
So upon disassembly I found out that something like a third of the 28 spokes were broken which explained why the wheel was so wobbly.  Once the rim was removed and cleaned I could see it had a Rigida stamping on it, I never knew a French company supplied Raleigh with rims.  Anyway the rim appeared to be in good shape, and the budget was limited so I was going to re-use it and lace it up with new spokes.  Although not before I would tear down the hub.  This was the first time I had taken apart an AW hub.  Removing the cones is easy enough although normal cone wrenches are a bit too fat to get at the cones, there is a special Sturmey Archer one you can get however.   The ball ring took a bit of effort to get off, I had to lace the wheel up first because I found it impossible to remove when it was just the hub by itself, I didn't have a vice or anything else to stop it from rotating. 

The wheel was built exactly the way it came except with new DT Swiss champion spokes with brass nipples and spoke washers underneath the heads, these are necessary to get proper bracing of the spoke head bend around the thin steel flanges of the hub.  It can be a bit difficult to get spoke washers, but I obtained mine from a specialist hobby store in Sydney http://www.casulahobbies.com.au, they are the 8BA washers which fit perfectly for normal sized spokes.  Also for your information, the spoke length on a 451 sized wheel with a AW hub and chrome steel Rigida rim is 218mm or thereabouts.  Your results may vary.

Ready to build with washers at the ready
Once the wheel was laced up removing the ball ring was relatively quick, I used a punch and hammer to tap away at the little ridges.  The steel is very hard as I didn't even make a mark after hammering at it for about 5 minutes beforehand.  Once the ball ring was out it was pretty easy to disassmble the hub, I had looked at drawings before hand and even watched a few videos.  They only have one set of planets, so as far as internal gear hubs go they are the most basic.


Inside you could tell that this was probably the only time it had ever been apart since it left the factory in 1975.  There was decades of grease and caked on gunk everywhere, the bearings looked very good, there was no scoring in the cones or races and no cracked teeth in any of the planets.  The clutch looked pretty good with no bad wear.  I just cleaned everything with some kerosene, wiped it down and put it back together again.  The seals at either end of the hub do their job really well, they are a labyrinth type seal which keeps the dirt and water out very effectively.  For a low maintenance city bike it's a perfect application, they are also supposed to have very little drag as well because there is no physical contact between either side of the seal compared to lip seals which rely on a flexible rubber lip which contacts the other surface.


Completed wheel ready to rock




Brass spoke washers

  The bearings got some fresh grease, as did the seals.  The rest of the hub was lubricated with ATF (automatic transmission fluid) which is on the thinner side, I've been using this stuff for the past few years.  The hub only requires a few drops, overfilling usually means it'll leak out of the gap between the ball ring and the driver, there is strangely no seal between the two other than a dust shield which goes behind the sprocket.  Once together I gave it spin, it had that classic sound which you only get from a Sturmey Archer, it's a clacketly clack sound that comes from the high and low pawls which is very distinct.  Music to a bike head's ears :)  Happy riding.



3 comments:

  1. Looks like a good job. I did that couple time.

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  2. You're a genuis. I don't have the guts to dismantle a three speed.

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  3. They may look complicated inside, but honestly a 3 speed hub is actually quite a simple device. Bike shops used to routinely rebuild these all the time. Once you get beyond three it starts to get exponentially complex where you arrive at something like the Rohloff...

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