SP dynamo hub failu...
 

[Closed] SP dynamo hub failure

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Seems to have failed. First one I had was notchy and didn't work properly so I had to dismantle the wheel and send it back. This one just stopped yesterday. I'd noticed the connector bit had migrated round because the skewer mustn't have been tight enough and the connector wire was looking a bit stretched. I reached down and moved the connector arm back a bit whilst still moving and it flickered and went off. I assumed it must have been the wires but I've just swapped to another dynohub wheel and it's fine. I've not fried it by moving whilst underway surely? Any ways of testing it? And is 3000 miles a reasonable life?


 
Posted : 08/02/2019 10:28 pm
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likely think is you have disrupted the contacts in the silly we plug thing if the cable pulled taut


 
Posted : 08/02/2019 10:35 pm
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I wondered. No amount of wiggling produces any power.

Do they have a 2 year warranty? Bought in April 2017


 
Posted : 08/02/2019 10:40 pm
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IIRC its a small plug you pull off the dynamo that you put the wires into. have you redone the connections in the plug?


 
Posted : 08/02/2019 10:58 pm
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Yes that was what I thought would have failed but if I plug it into another dynohub it works fine


 
Posted : 08/02/2019 11:13 pm
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Re-do the connections - they might just not be making full contact. I’ve had to do it mid ride with mine, on more than one occasion


 
Posted : 08/02/2019 11:17 pm
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Poking it with a voltmeter can help for testing, could show you if it is working or not.


 
Posted : 08/02/2019 11:23 pm
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Any ways of testing it?

As above, out a meter across the contacts, set to AC Volts and see if there's a reading when the wheel's spun.


 
Posted : 09/02/2019 10:08 am
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What's the axle size? There was a batch of SP dynamos for 15mm axles that had quality issues. Some people ran them for 10,000km with no problem others had theirs fail within 300km. Later production runs seem to have sorted it.

As @jameso says, stick a meter across the contacts.


 
Posted : 09/02/2019 10:15 am
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Meter shows nothing whereas the Alpkit hub is fine.

It's a 9mm QR disc hub from Spa Cycles. Cheaper than elsewhere but I'm beginning to wonder if they're a suspect batch. Certainly I've not found them reliable so far.


 
Posted : 09/02/2019 10:30 am
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I’ve had 2 SP dynamos. Both have failed (bearings) one at about 3000 miles the other at maybe 5000.
ISON distribution do a service exchange for £25 though. You get a brand new unit in return as far as I can see. My second one came in a box!


 
Posted : 09/02/2019 7:20 pm
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Ah, so maybe this is normal then. I suppose £25 isn't bad and I quite like building wheels! Is that open to public then or just trade?


 
Posted : 09/02/2019 10:21 pm
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And failing that any recommendations for a replacement? The other one I have is the Alpkit one


 
Posted : 12/02/2019 7:11 pm