Fitting a Sturmey Archer CS-RK3

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PaulM

Guru
Location
Portsmouth, UK
Decided to fit one of these to my Paseo so I could change gear when stationary. Pictures here: https://photos.app.goo.gl/dYHQkZOeH3H8fCw02

I got the hub from Practical Cycles and built it into a Mavic XC717 disc rim with double butted spokes. Trying to keep the weight down. I bought a Deore trigger shifter on sale from CRC. Fitting the hub into the vertical dropouts with non-turn washers puzzled me for a while but it does go when you get the axle flat sides oriented properly. However every time I remove the rear wheel I seem to have to realign the brake caliper. I've fitted a Marathon Greenguard tyre to lower the risk of p*ntures. The frame had a cable stop but it took me 3 goes to find a ferrule which fitted but didn't pull through. Connecting the gear cable to the cable anchorage for the indicator chain was not easy. I need a 7mm and an 8mm spanner for the nut and it took 4 attempts to position it accurately to have enough adjustment on the threaded cable connector which connects to the indicator chain.

In use the hub and the gear change have been silent and reliable thus far. However you need to stop pedalling when changing down which doesn't come naturally when you are caught out by an unexpected climb. Changing up can be done whilst pedalling and is quicker. I hoped it would give me confidence in the event of having to stop with little warning. However a downchange is probably equivalent to 2 cogs on the cassette and that isn't usually enough because I often need to come down 4 or 5 cogs to be confident of starting off. It seems a solid piece of kit. I carry around a box spanner anyway which will fit the 15mm axle nuts, but I don't normally carry the 7 and 8mm spanners needed for the cable bolt although these wouldn't be needed to take the wheel off for a puncture.

I am struggling somewhat with the seat recline angle. The photos were taken before I adjusted the ride height angle which further reclined the seat. This was needed to slacken the headtube angle. I will give it some time. The bike is a quality machine but I'm not used to SWB bents with seat angles down this low. I've also removed the front suspension fork to lower the front end and help with mounting and dismounting the bike and that's why I had to adjust the ride hight to compensate.

I have a front rim and hub on order so I can build a front wheel to take a Big Apple tyre. At the moment I'm getting nervous on damaged roads, the 40mm Racer on the front is not sufficient.
 
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I’ve just fitted one too to my Trice QNT, though for the purpose of getting higher gears - I had the low end sorted out nicely but could run out gears on the downhills. Now I have a 10” bottom and 120” top, 81 in total... should be enough! Not been out on the road much on it yet but initial impressions are good, it’s quiet, gear shift is straightforward, and whilst I thought the cable run might be a bit of a challenge with no dedicated cable stops, it was actually straightforward. SA make a bolt-on arm that allows you to run covered cable right the way to the toggle chain and hide the delicate bits under cover.

Like all small wheels it built up very quickly and was a doddle to true though there was a bit of play in the hub bearings that was a bit confusing at first. I was loathe to adjust the bearings as I’ve heard that Bad Things can happen to the gubbins inside if the hub is too tight.
 

Tilley

Über Member
Location
Bristol
Interesting I have also just fitted one of these to a Trice TNT but wasn't aware of the SA arm you refer to could you post a picture please. I assume that your QNT has rear suspension.
 
Interesting I have also just fitted one of these to a Trice TNT but wasn't aware of the SA arm you refer to could you post a picture please. I assume that your QNT has rear suspension.

See below... the cover (shown on and off) is perhaps a bit clunky but it keeps the crud off and I can’t see it when riding anyway! The end of the arm is threaded for an adjuster but I have no idea of the SA part number, whatever it is it’s bigger than a brake cable adjuster which I have bodged in place.

9D6E18E5-FFB1-4511-BB1D-C408C96D02C6.jpeg
53192018-67CD-4D21-96AA-25FD656B311A.jpeg


Parts obtained from SJS. Excuse the insulating tape to make the gear cable ferrule fit the brake adjuster...
 
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PaulM

Guru
Location
Portsmouth, UK
Update. I find the hub has a slow pick up which has an impact on starting off. The pawls seem to engage at only a handful of points in a rotation, so sometimes you have to choose between pushing off with the crank in the 1 o'clock position or in the 10 o'clock position. Neither is ideal. I want the crank in the 12 or 11 o'clock position for start off. This wouldn't be a problem on a trike though.
 
Yes, that’s what I ordered. Along with some other sundry bits which weren’t needed in the end (but which I bought just in case). You will need something to anchor the cable to the end of the fulcrum lever, a brake adjuster will fit even if it is too small to engage the threads. If I had thought about it I’d have run the locknut up the other side to secure it, but I can’t be bothered taking it to bits now...
 
I did wonder if a mid cable adjuster was a good idea.

Not really necessary - all the adjustment you will need is at the toggle chain - the barrel and locknut that you can see in my photo.
 
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PaulM

Guru
Location
Portsmouth, UK
Bit of an update. Getting on with the hub better now. I still change down on the RD at junctions but I know that if I have to stop I can change down further using the hub. Changing down is a 25% reduction, so about 2 sprockets worth. Changing up on hub is fab and can be done whilst pedalling whereas stopping pedalling to change down is not coming naturally. Think I've decided to swap out the triple for a double (one ring, one chainguard) and a titanium BB. I still need to fit a front mudguard now that I've swapped the fork. But that's a story for another thread ....
 
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