Author Topic: Shimano dynohub repair  (Read 1337 times)

Wothill

  • over the hills and far away
Shimano dynohub repair
« on: 24 March, 2021, 07:22:05 pm »
I finally got around to servicing the bearings on my DH-3N80 and got the technique and thing to be careful of on various Youtube videos. When I got to the stage where you bend the wire and connector up to get it through the hole in the plastic plate the connector just dropped off the end of the wire. In fact I think the wire must have been ready to break just a millimetre or so away from the connector because it really didn't get bent at all before it broke. Anyway, my question is, is there any way to re-join the wire to the connector. I tried electrical soldering but couldn't make it work - looks like the wire is steel perhaps so more difficult to solder. Has anyone managed to re-join the wire and the connector?

Kim

  • Timelord
    • Fediverse
Re: Shimano dynohub repair
« Reply #1 on: 24 March, 2021, 07:50:02 pm »
I've not yet had the opportunity to dismantle one, but it seems likely that the wire would be enamelled (so it can be wound into coils without short circuiting).  You could try scraping it with a bit of sandpaper or a small file or similar, and seeing if it then takes solder.

Wothill

  • over the hills and far away
Re: Shimano dynohub repair
« Reply #2 on: 24 March, 2021, 07:56:29 pm »
Thanks, Kim. That sounds like it's worth a try

Re: Shimano dynohub repair
« Reply #3 on: 24 March, 2021, 08:00:45 pm »
Where has it broken? On my Shimano Dynamo hub the wires are connected to metal prongs that spring fit into the plastic body.







Any pictures?

Re: Shimano dynohub repair
« Reply #4 on: 24 March, 2021, 08:24:47 pm »
The Shimano 3N80 has the "old style" single wire connector. I owned the preceding model, the 3N71, that I didn't use because it had a cone design flaw that made the cone vulnerable to cracking, and spare cones therefore impossible to source. So I scraped the silver-coloured "enamel"/coating of the wire, and it showed a copper coloured core wire inside.

Based on my experience with the 3N80 (I own 3 and have serviced 2 of them), I find it highly likely that the wire running from the stator to the connector, has an enamelled copper wire too.



--
Regards

Wothill

  • over the hills and far away
Re: Shimano dynohub repair
« Reply #5 on: 24 March, 2021, 08:34:33 pm »
Mine is a different hub with only one wire. In this picture I have removed all the parts you show separately and the bit I am holding is the connector which used to be on the end of the wire.

Wothill

  • over the hills and far away
Re: Shimano dynohub repair
« Reply #6 on: 24 March, 2021, 08:38:13 pm »
The Shimano 3N80 has the "old style" single wire connector. I owned the preceding model, the 3N71, that I didn't use because it had a cone design flaw that made the cone vulnerable to cracking, and spare cones therefore impossible to source. So I scraped the silver-coloured "enamel"/coating of the wire, and it showed a copper coloured core wire inside.

Based on my experience with the 3N80 (I own 3 and have serviced 2 of them), I find it highly likely that the wire running from the stator to the connector, has an enamelled copper wire too.
Thanks, I think you are right. I will have a go at taking off the coating tomorrow. If I can get down to copper, I should be able to solder it to the connector, or if too short, I might be able to solder on a new bit of wire to make it reach.

Re: Shimano dynohub repair
« Reply #7 on: 24 March, 2021, 08:41:06 pm »
Mine is a different hub with only one wire. In this picture I have removed all the parts you show separately and the bit I am holding is the connector which used to be on the end of the wire.


From what I can see the metal prong is still attached to the wire?  In that case you should be able to just fit that (prong) back in the plastic body. Do you have a bigger picture with a slightly better focus?

Wothill

  • over the hills and far away
Re: Shimano dynohub repair
« Reply #8 on: 24 March, 2021, 09:01:41 pm »
Mine is a different hub with only one wire. In this picture I have removed all the parts you show separately and the bit I am holding is the connector which used to be on the end of the wire.


From what I can see the metal prong is still attached to the wire?  In that case you should be able to just fit that (prong) back in the plastic body. Do you have a bigger picture with a slightly better focus?
Sorry I was having difficulty getting the right parts in focus. These are slightly better I hope
https://flic.kr/p/2kGHwaX
https://flic.kr/p/2kNQAJd

Wothill

  • over the hills and far away
Re: Shimano dynohub repair
« Reply #9 on: 24 March, 2021, 09:09:38 pm »
Still having difficulty with the size of the images


Re: Shimano dynohub repair
« Reply #10 on: 24 March, 2021, 09:59:38 pm »
Ah can see now. I wonder if soldering then shrink wrap over to strengthen might work?

Wothill

  • over the hills and far away
Re: Shimano dynohub repair
« Reply #11 on: 24 March, 2021, 10:06:41 pm »
Ah can see now. I wonder if soldering then shrink wrap over to strengthen might work?
Yes, the difficulty is going to be in soldering the wire to the connector since the wire seems to have a stubborn coating on it. I'll take a file to it in the morning I think. Shrink wrap is a good idea!