2 replies [Last post]
Scott's picture
Joined: 10/11/2015
Posts: 3

Hello all!

I have a 1939 BMW R61. I am currently having issues with the charging system, the battery completely discharges after 6 or 7 miles. Does anyone have experience upgrading to a solid state voltage regular or even upgrading to a 12 v system? The bike has been in the family for quite a few years and I never imagine selling it on so an looking to make it as reliable as possible to make the most of it.

Any comments recommendations would be greatly appreciated, as expected I'm finding it difficult to find information online.



luca.stere's picture
Joined: 05/23/2013
Posts: 43
Try to read the solutions

Try to read the solutions used on Ural M72, it is almost the same bike as the BMW R61. For example you can use a 6V electronic regulator (if that is the problem), also I think you can always use parts for the generator (rotor, coils) from Ural M72. Just search the solutions used for Ural M72 and try to verify if you can used them to your bike.

Maybe this solution is good for you: http://moto-boxer.com/product_info.php?cPath=24_42&products_id=1648 .

yameml's picture
Naaldwijk ,The netherlands
Joined: 01/16/2014
Posts: 2
If you want to keep it

If you want to keep it original ,it is a Bosch dynamo that can be regenerated together with an electronic regulator it should work fine.mine is done last winter in a german workshop. new wires from and to the accu and a good ground cable .


Hans de Haan The Netherlands

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BMW r61 owner

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