The Micro Bike

[Chris S]

Can I fashion a replacement for the chain - perhaps tie the cable to the one remaining link of the chain?

No. A few of the chain links need to slide in and out of the axle-nut.

I'm not sure how to proceed. Can this chain be dismantled and moved over to the original indicator?

Jewellers have chain splitters small enough to do this. However they would charge more than the cost of another chain.

 

[dimrub]

I measured the old indicator. It has 64mm from the thread to the mark, which is red. This makes it an HSA490, according to SB. Aliexpress don't have it. Ebay doesn't have it. Amazon doesn't have it. Various UK-based stores claim to have it, but charge outrageous fees for shipping (£7.99 for the part, £30.00 for shipping, it's good news then that they deduct the VAT when shipping abroad).

If someone who is UK-based is willing to see me complete this project, consider PM-ing me. I'd order the part to your address, you can then put a stamp on an envelope and mail it to me, and I'll PayPal the cost.

 

[dimrub]

Also, I just realized that what I have is a 5-speed hub - and of course, the shifter I got is a 3-speed. Arrgh.

 

[Chris S]

I've just got this reply from the Sturmey Archer Facebook group. You could get more advice there.

Is it possible to join the rear half of the chain on the right to the one on the left? If so are there any videos on how to do this please?

Yes, a hammer and punch, or alternatively filing off one head, will deal with removing the rod from the new chain. When re-joining the chain a small nail can be cut down to make a very good replacement rivet which can then just be hammered flat on its cut end to retain it.
This is the approach I recommend to anyone seeking a new 4 speed rod when their only problem is a broken chain.

 

[dimrub]

I've just got this reply from the Sturmey Archer Facebook group. You could get more advice there.

Is it possible to join the rear half of the chain on the right to the one on the left? If so are there any videos on how to do this please?

Yes, a hammer and punch, or alternatively filing off one head, will deal with removing the rod from the new chain. When re-joining the chain a small nail can be cut down to make a very good replacement rivet which can then just be hammered flat on its cut end to retain it.
This is the approach I recommend to anyone seeking a new 4 speed rod when their only problem is a broken chain.

Wow, that's interesting. I've got nothing to lose here, so I'll try that, worst case I'll destroy that indicator that I have no use for anyway. Thanks!

 

[dimrub]

So I managed to take off the new chain, and take the remainder of the old chain off the old spindle. I even managed to kind of put it all back together using the old rivet, but I'm not sure it'll hold - it's too late for me to think straight, so I'm leaving this for tomorrow me to handle:

 

[Chris S]

Also, I just realized that what I have is a 5-speed hub - and of course, the shifter I got is a 3-speed. Arrgh.

You may still be able to use it as a 3-speed if the pull-lengths are the same.

 

[Chris S]

So I managed to take off the new chain, and take the remainder of the old chain off the old spindle. I even managed to kind of put it all back together using the old rivet, but I'm not sure it'll hold - it's too late for me to think straight, so I'm leaving this for tomorrow me to handle:

View attachment 725604

How did you get the rivet out? I want to see if I can rejoin a broken chain.

 

[dimrub]

How did you get the rivet out? I want to see if I can rejoin a broken chain.

On the old chain, I just filed it down then pushed a small screwdriver inside the link and it all fell apart. On the new chain I pressed on the end of the rivet with pliers, then pulled it out from the other side.

 

[FrankCrank]

Packages have arrived today, the brake levers, the clamps for the frame, the chain indicator. Hurray, I thought, test ride today. Yeah, sure.

Brake levers - no problem, on they went, and the grips, and everything is tightened up and tidy. And the front brakes are done, wonderful.

The clamp had to be drilled out, but that's ok.

View attachment 725579
So far so good. Then it was the turn of the chain indicator. I tried pushing it into the hub, but it wouldn't go. I was pretty sure that nothing was left there, so what is the reason? Luckily, I retained the original indicator, the one with the broken chain, and a brief look at both side by side provided an immediate answer:

View attachment 725580

Yup, different diameter of the indicator. So here you go, dear proponents of the intelligent design theory. No universe, in which the same company produces chain indicators in two different diameters, because why the heck not, can be said to have been designed intelligently.

I'm not sure how to proceed. Can this chain be dismantled and moved over to the original indicator? Can I fashion a replacement for the chain - perhaps tie the cable to the one remaining link of the chain? Should I just try and order a new chain indicator - of the correct diameter this time?

So close. So damn close.

P.S. And, of course, Sheldon Brown has an article on the subject, that fully explores the variety of spindles out there.

Those later, thinner spindles look like a solution to a problem that didn't exist.

Another example - this type of selector works perfectly well, has done for decades........

..........so why bother adding more complication, like this, when it's not needed?

And a typical SA hub kit now looks like this

Apologies to the OP, had to get this off my chest. I'll have a lie down now.

 

[dimrub]

Aand it's done.

I've done all I could for this cute little buddy. And by that I mean that it has a 3-speed shifter and a 5-speed hub. The gears switch alright, but it doesn't have the original range. And, of course, the situation with the shifter is the same as with the indicator spindle: the part itself costs peanuts, the shipping is prohibitive. So I'm leaving it as it is for now.

As mentioned, the bike cost me around 50 euros, and the parts - around 100, so 150 euros for a great condition (if I say so myself) vintage Micro. I had some interesting challenges, and I also learned to appreciate my Brompton so much more. Granted, even though they were a product of the same era, their respective creators were trying to solve two very different problems. Peter Radnall, the creator of the Micro, was trying to create a good commuting folder, for cheap. Andrew Ritchie, the father of the Brompton, was going for the best folder, period. They both succeeded at their tasks. Brompton is so much more fun to ride.

 

[Chris S]

What gears select - fifth, third and second?

 

[dimrub]

What gears select - fifth, third and second?

I don't think I can tell. With the 3 it's simple: the second is the direct connection, so pedals and the wheel rotate in unison, the third is easier, the first is harder. With the 5 it's trickier to test. I'll try tomorrow and see whether I can make any sense of it (for example, whether there's more pull on the chain when the shifter is on 3).

 

[Chris S]

If the 3-speed shifter is in 2nd gear and the axle and indicator rod ends are level then you will have direct drive (3rd gear in a 5-speed hub).
If moving the shifter into 3rd gear releases all the tension in the cable then the hub will shift into 5th gear by default.
I'm guessing that moving the shifter into 1st gear will produce just enough tension to select 2nd gear in a 5-speed hub.

 

[dimrub]

A couple more photos in daylight.