Electrifying my Dahon Mu Uno

tonythebrit said:
the Sturmey Archer S2C rear hub is designed to be fitted to a bike with regular horizontal chainstays, which my Mu Uno has not got.
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Can you post a pic of the dropouts? I guess I assumed since it's a single speed chain, they'd need to be horizontal unless you had a chain tensioner. So it's not the same as this model?
https://www.bikefolded.com/dahon-mu-uno-review/
 
Many thanks to your suggestions. The only thing is that Mu Uno doesn't have chainstays or seatstays as such, just a single frame member that slopes down to the rear dropouts, with a litle gizmo on top just above the dropouts where the brake arm of the (Shimano) coaster hub would attach. My first modiication consisted of a metal strut connecting the brake arm of the S2C hub with this gizmo, by means of nuts & bolts at each end. It looked a bit amateurish, but I'm sure it would have worked. I still think that the answer lies in whether or not the orientation of the brake arm of the S2C can be altered. Watch this space, I think I'm on to something!
 
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Yes, it's the same model as in the photos in the link. You can see the coaster brake arm attached to the frame in the 4th photo.
 
Take a look at this advertisement for a Sturmey Archer brake arm, then click on the small picture, which shows you what the rear of the assembly looks like.
[urlhttps://www.sjscycles.co.uk/hub-spares/sturmey-archer-brake-arm-cone-assembly-for-s2c-hsh495/][/url]

Now look at this item on Youtube, especially Minute 5-24
[youtubehttps://www.youtube.com/watch?v=1G1RaKQU5J0][/youtube]

Whar do you think about that?
 
tonythebrit said:
Take a look at this advertisement for a Sturmey Archer brake arm, then click on the small picture, which shows you what the rear of the assembly looks like.
[urlhttps://www.sjscycles.co.uk/hub-spares/sturmey-archer-brake-arm-cone-assembly-for-s2c-hsh495/][/url]

Now look at this item on Youtube, especially Minute 5-24
[youtubehttps://www.youtube.com/watch?v=1G1RaKQU5J0][/youtube]

Whar do you think about that?
Click to expand...

I don't see how that is locked into a position by the axle flats. It doesn't seem likely that they rely on just friction from the locknut. The cone assembly is probably keyed, but you would have to take it apart to find out. I would look into adding a vertical bar to the existing torque arm as shown here:

41dBkjj2yFL._AC_.jpg


TrqRev3.jpg
 
tonythebrit said:
I reckon it means that it's possible to turn the brake arm through 90 degrees!
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You don't need to. Whichever orientation it ends up in, you can still add an extension piece, just like is used with a hub motor torque arm, so as long as that's anchored to the chain stay, it should work.
 
If you look at the fotos in the Bikefolded link, you will see that the Mu Uno doesn't really have round-section rear frame members, just one quite large oval-section member, ending in rear-facing horizontal dropouts. I still think that attaching various bars by means of jubilee clips (you might know them as "hose clamps ") is not much better than the metal strut I mentioned I had fitted - and in any case, both methods look just a bit amateurish. I strongly feel that changing the orientation of the brake arm from horizontal to vertical will ultimately look much better.
 
tonythebrit said:
If you look at the fotos in the Bikefolded link, you will see that the Mu Uno doesn't really have round-section rear frame members, just one quite large oval-section member, ending in rear-facing horizontal dropouts. I still think that attaching various bars by means of jubilee clips (you might know them as "hose clamps ") is not much better than the metal strut I mentioned I had fitted - and in any case, both methods look just a bit amateurish. I strongly feel that changing the orientation of the brake arm from horizontal to vertical will ultimately look much better.
Click to expand...

I can't wait to see the final conversion! :thumb:
 
So, I bit the bullet and went for it! With the knowledge gained from the Youtube vid, I removed the locknut & brake adjuster nut frrom the non-drive side (with the wheel clamped horizontally of course). The brake arm just lifted off, I rotated it 90 degrees clockwise and replaced it, with the 4 protrusions engaging correctly, but with the arm now orientated vertically rather than horizontally. I replaced the nuts, and then checked the wheel's positioning on the bike. The arm aligned perfectly with the bracket on the bike, except that I had to drill a new hole for the securing bolt and cut about a half inch excess metal off the end of the arm. Bingo, Job done!!
 
tonythebrit said:
So, I bit the bullet and went for it! With the knowledge gained from the Youtube vid, I removed the locknut & brake adjuster nut frrom the non-drive side (with the wheel clamped horizontally of course). The brake arm just lifted off, I rotated it 90 degrees clockwise and replaced it, with the 4 protrusions engaging correctly, but with the arm now orientated vertically rather than horizontally. I replaced the nuts, and then checked the wheel's positioning on the bike. The arm aligned perfectly with the bracket on the bike, except that I had to drill a new hole for the securing bolt and cut about a half inch excess metal off the end of the arm. Bingo, Job done!!
Click to expand...

Nice. If you have time, a pic might add value to other folks that try the same conversion. :bigthumb:
 
E-HP said:
Nice. If you have time, a pic might add value to other folks that try the same conversion. :bigthumb:
Click to expand...
Ditto on the picture
 
I'm not quite sure how I did that, my PC has been misbehaving. Anyway, hope those pix posted OK. I didn't show the whole bike, there are some bits missing at the moment - no tyres or tubes (except for an old tube to protect the new rim), and no chainwheel or chain.
 
The first view is before assembling the brake arm to the hub - you can see the 4 protrusions referred to in the Youtube vid, and just about identify where they will fit after rotating 90 degrees. The other views are after assembly to the bike.
 
While I'm waiting for a few more components for my Mu Uno, I'll digress slightly, and I'm sure the Moderators won't object. In addition to being a bike nut, I also like to keep pretty fit - I work out, and for cardio I use my Spinning Bike. It's based on a re-tired (or should that be "re-cycled") Claud Butler 24-speed hybrid - minus the front wheel and all brakes & cables, derailleur hanger, front changer, large & small chainrings, plus anything else I could safely remove. It's now only got a single gear, using the middle chainring and small cog (giving the best chainline), and let me tell you, shortening and re-joining a chain that's several years and many miles old is a really messy job!.The Turbo Trainer frame that it's mounted on cost me about £40 from Halfords (national motor & bike retailers). Peloton - Who needs it!
 

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I like to use Zwift, but even Youtube videos of bike rides can relieve the boredom. However, you would have to scoot it back from the wall a bit and add a TV in front of it. Maybe you could mount a tablet on the handlebars.
 
You can't see in the foto, but just above the handlebars there's a small shelf with an audio cassette player with a USB port, so I can play back tracks from my MP3 player. I also have a tablet (which I haven't used in ages), so maybe I can resurrect that, and spin through some of the Tour de France stages (if only in my mind). Usually, I grit my teeth and just spin and dream!
 
After having a new rear wheel built for the Dahon, when I tried to fit a tyre & tube on it (first, the original Schwalbe Marathon Racer, and then a Schwalbe Kojak I'd bought recently), neither tyre would fit and they just seemed to be far too small. It was then I realised my dumb mistake - the original rim had been a 406, both tyres were 406, and the replacement rim I'd bought and had fitted was, yes you guessed it, a 451. Dohhh!! I suppose I could have kept the wheel like that, but I found that the choice of tyres for 20" 451 rims is very limited. So I decided to overcome the problem by having the wheel rebuilt with a new 406 rim. When I get it back, hopefully sometime next week, I'll post a new pic of the bike.
 
I thought it was about time I got up-to-date with my Mu Uno project (assuming there's still somebody out there following this thread)! I got the rebuilt 406 wheel back, and today I fitted it with a 2" Big Apple, and it looks really good on the bike. I've ordered the Swytch setup, but at the discount price, so I have plenty of time to get the bike ready exactly as I want it.
I've been doing loads of research on E.S., and there's one important aspect now I'd like advice on. Now, bearing in mind that the Mu Uno has an alloy frame and forks, but the Swytch front wheel motor is a relatively pipsqueak 250W, should I still play safe and fit a Torque Arm (or arms)? The bike has fender eyelets, so fitting should be straightforward. Advice please.
 
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