This new-to-me (but bought used, apparently only 400km) SON hub dynamo started making this rattling sound after a very long ride with a few rather rough gravel and sand segments. It worked fine & quiet beforehand.
The sound changes when the lights are switched on & off, with it being louder with the lights off and slow speed (not sure if its just not audible die to other noises at high speeds or if it really gets quieter).
I'd be grateful for any ideas what I could try in order to fix it!
by thebertl
3 Comments
There’s not much going on inside them that could make that noise. Have you carefully checked it’s not the bike making it? They do cause some vibration.
From Peter White Cycles: “Leave the hub alone! If you bring your bike into your local shop for a tune-up, tell the mechanic to leave the hub alone! If the mechanic thinks he knows better than anyone else about how the axle on a SON hub should feel when turned, find yourself another bike mechanic. Only if you hear a scraping sound (an extremely rare condition which means there’s corrosion on the dynamo core) while turning the axle does the hub require service. And neither you nor your local shop will be able to perform that service.” I have a SON front hub and I have ridden a lot of gravel with no difficulty or weird noises, but it’s possible that you got some moisture incursion and corrosion. You might call Peter White and ask about service, they’re very helpful on the phone (not so much by email). [https://www.peterwhitecycles.com/schmidt.php](https://www.peterwhitecycles.com/schmidt.php)
Where are you located?