Author Topic: SON dynamo service  (Read 2459 times)

T42

  • Apprentice geezer
SON dynamo service
« on: 09 September, 2019, 08:54:10 am »
Chum of mine has a SON dyno wheel that grates when he rotates it.  He used it on PBP 2011 so it's at least 8 years old.

He's asking me if he should try to service the bearings himself. Sending it back to SON is likely to be a royal PITA and cost as much in the end as new kit.

What thinketh the panel?
I've dusted off all those old bottles and set them up straight

Re: SON dynamo service
« Reply #1 on: 09 September, 2019, 09:31:12 am »
it is probably grot inside the generator that is making the noise, e.g. bits of rust between the stator and the magnets. The bearings could be fine.

You don't say what model of hub he has but there is one that is easy (ish) to service; the innards unscrew from the RH side. However all the other SON models are pigs to work on.

If you want a SON then a factory service will make the old hub like new and at that price it would be very cheap for a new SON hub. However you can buy an alternative ( cheaper, less good) hub for about the same money.

cheers

T42

  • Apprentice geezer
Re: SON dynamo service
« Reply #2 on: 09 September, 2019, 09:48:50 am »
Thanks, Brucey.  I don't know what model he has - come to that, I'd be hard put to remember which I have.

Anyway, I'll pass it on. Ta.
I've dusted off all those old bottles and set them up straight

Re: SON dynamo service
« Reply #3 on: 09 September, 2019, 09:59:21 am »
It cost about £64 to have my old black-barrel one serviced and returned via SJS.  It now even has a breather hole inside the hollow axle.

T42

  • Apprentice geezer
Re: SON dynamo service
« Reply #4 on: 09 September, 2019, 10:31:54 am »
Just checked mine (model #K179) - still silent and developing 8.5v when I spin it by hand. 12 years old with 8 of service.

ETA Thanks, Ian H - duly passed on.
I've dusted off all those old bottles and set them up straight

pdm

  • Sheffield hills? Nah... Just potholes.
Re: SON dynamo service
« Reply #5 on: 09 September, 2019, 12:18:10 pm »
IMHO, don't service it yourself. I have 3 SON 28s that have done many miles. about 3 years ago, one developed slight loosening/roughness of the bearings after 5 years of very heavy use - sent it off to SON and got it back as good as new free of charge! I would have gladly paid the £64 for the years and distance it had given me nonetheless...

Wowbagger

  • Former Sylph
    • Stuff mostly about weather
Re: SON dynamo service
« Reply #6 on: 10 October, 2019, 04:13:06 am »
Mine is 13 years old, has done almost 39000 miles and has had to put up with my great bulk, which has been in excess of 105 kg for all of that time, and 10kg more than that for most of it. I have been advised not to get it serviced until it shows signs of deterioration.
Quote from: Dez
It doesn’t matter where you start. Just start.

rower40

  • Not my boat. Now sold.
Re: SON dynamo service
« Reply #7 on: 10 October, 2019, 05:18:23 am »
Dearly beloved,

We are gathered together to give thanks for this wonderful item of engineering, which lighteth our way, yea verily, e'en when all batteries have shuffled off this mortal coil...
Be Naughty; save Santa a trip

Re: SON dynamo service
« Reply #8 on: 10 October, 2019, 10:19:37 am »
Just checked mine (model #K179) - still silent and developing 8.5v when I spin it by hand. 12 years old with 8 of service.

IIRC ~K179 is the Stvzo approval number, rather than the model number per se.  The ~K number does vary with the model though, since each (electrically) different generator needs a separate approval.     Is yours a 28 Klassik?



If so this is one of the few that can be opened up without undue difficulty.  Using the appropriate tool all the gubbins unscrews from the RHS.

After a certain date all SON models have their 'pressure compensation system' which comprises a long coiled plastic vent tube connected to a drilling in the axle. The basic idea is that  water can't into the hub through the vent, even though the air volume in the hub is contracting and expanding with changes in temperature.  If you send an older SON in for a factory service (outside the five year(?) warranty period) they can upgrade the hub to the newer style vent.


cheers

rogerzilla

  • When n+1 gets out of hand
Re: SON dynamo service
« Reply #9 on: 10 October, 2019, 04:28:56 pm »
Chuck it and buy a Shimano one  :demon:
Hard work sometimes pays off in the end, but laziness ALWAYS pays off NOW.

Wowbagger

  • Former Sylph
    • Stuff mostly about weather
Re: SON dynamo service
« Reply #10 on: 10 October, 2019, 10:47:30 pm »
Dearly beloved,

We are gathered together to give thanks for this wonderful item of engineering, which lighteth our way, yea verily, e'en when all batteries have shuffled off this mortal coil...

The key question is - does a SON dynamo have an immortal coil?
Quote from: Dez
It doesn’t matter where you start. Just start.

Paul

  • L'enfer, c'est les autos.
Re: SON dynamo service
« Reply #11 on: 10 October, 2019, 11:23:17 pm »
Dearly beloved,

We are gathered together to give thanks for this wonderful item of engineering, which lighteth our way, yea verily, e'en when all batteries have shuffled off this mortal coil...
... In the name of going farther and of the SON and of the oily spirits...
What's so funny about peace, love and understanding?