Sturmey Archer / derailleur combination gears

[stevemoulton]

Now that looks interesting , want to do this on my sa 3 speed moulton , i,m quite ok technically , but dont know what all the parts are called , or where to get them , iv'e got loads of rear mechs , n shifters , but not the screw on block thing ?? for the cogs

 

[classic33]

Why stop there, a double or triple crank as well
Sheldon Brown did this , I'd insert a hyperlink here but don't know how to. He got up to 60 gears using a 4 SA. 5 Screw on and a 3 Crank I seem to remember.
Why? dunno, probably cos he could, Be good for bragging though ( eg nah mate this ones a 60 speed)

Got a 105 speed in the shed.

 

[aussiemusicman]

On my 63 Mercian Superlight. One can screw on a Normandy/Maillard large spline freewheel onto a threaded driver BUT you must immobilise the Maillard freewheeling spawls, as the SA hub freewheeling action will compete and make for strange running! Access to tthe SA r/h spindle inner locknut is still restricted. Just having 4 sprockets helps here. Do not be tempted to screw on a REGULAR small splinded freewheel as it's impossible to dismantle because of the SA freewheeling!! I use 15 to 24T 4 Maillard on the AW hub with 26/42 chainrings. Great for touring. The front 26T make an extremely low first gear and rather too much lost motion on initial take up when one starts peddaling.3 gear levers provokes a lot of interest!

 

[tyred]

It lives! I did a 2 sprocket conversion on an old road bike that I had built with a Sturmey a few years ago. I would have liked to have use 1/8" chain but had no Cyclo mech but have lots of 70s Huret Mechs so bought 2 x 3/32" Shimano hub gear sprockets. As it turns out they appear to be a little thicker at the base than the SA ones so had to grind a little of them so I could refit the spring clip properly.

I didn't try to grind or modify the teeth as people have successfully rode derailleur geared bikes for several generations before any of this was done and with only two sprockets, it was always going to be straightforward to change. I also had a NOS 3/32" chain which is the traditional pinned and bushed type with protruding rivets and old derailleur systems used the rivets to catch side of the sprocket to aid shifting. A modern chain may be more flexible but it probably wouldn't work as well as the rivets don't protrude.

So I now have 2 sprockets 3 teeth apart, a DT Huret friction shifter to work the Huret mech, and the bar mounted trigger to operate the Sturmey, a gear range of ~40" - 83" and after doing 50 hilly miles on it yesterday it all works beautifully although I think I need to tweak the limit screws very slightly on the mech. The derailleur changes well, much better than I thought it might, the gear range is practical and it splits the gaps in the normal Sturmey gearing and also gives one lower and one higher gear than I had before. After a few miles it becomes intuitive actually and you can "half-step" the gearing or take the easy option and just select "high" or "low" with the derailleur depending on terrain and then use the Sturmey as normal.

Now, I have a 42/52 cottered chainset in good condition hanging up in the garage - do I need 12 gears as part 2 of my experiment...

 

[aussiemusicman]

 

[tyred]

Bike is a mid '70s basic Kalkhoff skip rescue. It's nothing special but the oddity is that it appears to be built to take 26 x 1 3/8" (perhaps 26 x 1 1/4" originally) wheels which I wouldn't have expected from a German manufacturer. It originally had 5 speed Sachs Derailleur setup. The wheels that came with with it were mangled and I decided on a 3 speed convestion after buying that back wheel for £2 at a car boot sale. I had to replace the axle with a longer one to suit the 126mm dropouts. I put a new basic alloy wheel on the front in the interests of stopping and put ~1,500 miles on it over the winter of 2013/2014 and then I left it lying in the garage until I decided to have a play with this conversion. 1 x 19t and 1 x 22t Shimano hub gear sprocket slightly modified to fit, Sachs-Huret mech with matching downtube shifter, I'm very happy with outcome after a 50 mile test ride on Sunday but I probably will replace the rim with an alloy one at some point and ideally repaint the frame.

But the priority - get rid of that awful San Marco Rolls saddle. I had forgotten how much I hate them.

 

[User42423]

I've done it again. I had a spare Rudge Pathfinder frame, originally built in about 1967 for a derailleur 4 or 5 speed gear set up.

A couple of weeks ago I found a NOS 1990 AW hub that the vendor was prepared to build into a 27 x 1 1/4 wheel at a very reasonable price. Since I had also just found a threaded SA driver it seemed silly not to build a tourer with combination gears. (At least, it seemed a good idea to me!).


Late 60s Phase III Rudge Pathfinder rebuild with SA/Derailleur combi gearing by CraigWales, on Flickr

It has been surprisingly simple. 3 speed 1/8 chain screw on blocks are still quite widely available and not very expensive at all. ( I did think of hanging on for a cyclo item, but a 2 speed used one just went for £45 on fleabay, so I didn't bother). Almost everything else I needed was lurking in the shed on the "I better get that because they are hard to find now, and it will come in handy" principle. (I have tried explaining this theory to my wife, but with little success.). The trickiest job was disassembling the SA hub to fit a longer axle, but there is so much really good advice available on stripping SA hubs on u-tube that I managed it quite easily ( Except I had to reset the cones twice because I didn't pay attention to the fine detail about setting the drive side cone first or the gears won't work !).


SA AW NOS hub with 3 speed derailleur block by CraigWales, on Flickr


Longer axle installed - 9 gear set up by CraigWales, on Flickr

Another week or two will see it finished and out for a spin, a nice incentive to get back on a bike as the weather improves! Has anyone else tried this? I am not clever enough to work out gear ratios, but, with luck, I should have 9 to play with that are all different .

I'll let you know!

I was interested to read your article on converting a three speed into a multi speed mount. I have also built up a 1950s lightweight into a hybrid tourer. The machine original came with a 3-speed S/A & a Cyclo twin chain-set. Sadly, the chain-set wasn't viable. I have now fitted a Cyclo double sprocket & a Campag derailleur. Although a good combination, it is still a tad too low geared.

 

[classic33]

View attachment 103937
I was interested to read your article on converting a three speed into a multi speed mount. I have also built up a 1950s lightweight into a hybrid tourer. The machine original came with a 3-speed S/A & a Cyclo twin chain-set. Sadly, the chain-set wasn't viable. I have now fitted a Cyclo double sprocket & a Campag derailleur. Although a good combination, it is still a tad too low geared.

How high a gear do you want?
Setup is a 42/52/62 on a 7-speed freewheel mounted on an SA 5-speed hub. A top of 229 gear inch's in the current setup.

 

[Bobtoo]

Let's not get silly. I thought in the 60s that 4 gears were a bit posh, and 9 seems more than enough for the UK. Not room for a 5 speed block without fouling the frame and yes, I did think about a double chain ring on the front, but quite like the nice retro alloy 48 tooth that's on now. Anyway the 9 speed works so well that just one more really, really, low gear would be enough, leaving two in hand for weekends.

The nine speed works very well, two of the freewheel cogs are slightly larger than the original and one smaller, giving a few more low gears and a couple of higher then the original 3 speed. I tend to linger in the SA three speed "medium" using the low and high when required, That still leaves me lots of options on hills, and just switching the SA to "low" at the lights gives me one of three gears all suitable for moving off in, without having to move off first..

I have to admit to using this concept before. In the late 60s I drove one of these for a living:


WWB 902J, Foden S50 Tilcon by ronnie.cameron2009, on Flickr

The Amey Roadstone (ARC) version had a four speed conventional gear change on the floor and a second three speed gear box working from a compressed air change lever on the steering column. And yes, that is as complicated as it sounds. We used all 12 gears as routine and changing both gear boxes at once was quite a procedure, involving quadruple de-clutching ( In 3rd on the main box and high on the three speed you had to change the 4 speed UP in sequence to changing the 3 speed DOWN to get what was actually 10th gear. Much easier to do than to explain!

I suspect the low revving characteristics of the wonderful Gardner engines made the gear changes possible. I only once missed a change, on the looooong uphill road on the boundary of the Duke of Bedford's estate. It took about 15 minutes at 4 miles an hour before it got flat enough to change up and gain speed. Embarrassing! If you were in the two mile tailback following I would like to take this opportunity to apologise. Look on the bright side, it was a lovely sunny day.

Anyway, 12 on the bike is quite enough, more would just be showing off.

I came across this video tonight and it made me think of this thread. It looks like hard work

View: https://www.youtube.com/watch?v=5pwhm_xoDiY

 

[TheDoctor]

Ooooh a two stroke diesel!

 

[raleighnut]

Lovely sounding motor but the gearbox is just a half-gear 'split' box (similar to an overdrive in each gear)

 

[tyred]

The challenge: put a David Brown 995 through all 12 gears in sequence

 

[porteous]

Nice.