I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can spend the summer building up a wheel ready for the winter commute. Obviously I will need new lights and get the wiring right, but that is not the purpose of this post. When I took the nice shiny lump out of the box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
Is it likely that the cones are too tight and need to be slackened off a bit, I assume that the stepping sensation could be due to the magnets and rotors, but I would like to get confirmation that this is not a problem with the bearings.
-- Don Whybrow
Sequi Bonum Non Time
If you're happy and you know it, clunk your chains.
I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can spend the summer building up a wheel ready for the winter commute. Obviously I will need new lights and get the wiring right, but that is not the purpose of this post. When I took the nice shiny lump out of the box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
Is it likely that the cones are too tight and need to be slackened off a bit, I assume that the stepping sensation could be due to the magnets and rotors, but I would like to get confirmation that this is not a problem with the bearings.
Any hubdynamo will be extremely notchy out of the box and hard to turn with just your fingers. If you build it into a wheel and mount the hub solid in a fork and give it a spin it should behave as a normal wheel untill it comes to a stop and the notchiness takes over. On stopping it should overshoot a bit, if it doesn't turn back at all the bearings are to tight
I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can spend the summer building up a wheel ready for the winter commute. Obviously I will need new lights and get the wiring right, but that is not the purpose of this post. When I took the nice shiny lump out of the box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
Is it likely that the cones are too tight and need to be slackened off a bit, I assume that the stepping sensation could be due to the magnets and rotors, but I would like to get confirmation that this is not a problem with the bearings.
I haven't handled the Shimano hub, but the Schmidt hub does the same thing. When it's rotating in a built wheel, the attractions and repulsions largely cancel each other out.
Is it likely that the cones are too tight and need to be slackened off a bit, I assume that the stepping sensation could be due to the magnets and rotors, but I would like to get confirmation that this is not a problem with the bearings.
It is almost certainly the magnets you can feel - especially as the hub is new.
Once built into a wheel, you won't feel this stiffness.
I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can spend the summer building up a wheel ready for the winter commute. Obviously I will need new lights and get the wiring right, but that is not the purpose of this post. When I took the nice shiny lump out of the box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
Is it likely that the cones are too tight and need to be slackened off a bit, I assume that the stepping sensation could be due to the magnets and rotors, but I would like to get confirmation that this is not a problem with the bearings.
Scroll down about 2/3 of the way for a very good answer to your question. Mr. White's musings on this page refer to the SON (Schmidt hub dynamo), but the idea is the same. The only difference seems to be that attempting to adjust the Schmidt dynamo hub will cost you a lot more money than similar tinkering with a Shimano product. FWIW, I examined a Schmidt dynamo hub at Peter White's establishment a while back, and found the "turning in steps" feeling to be at least as pronounced as with my Shimano dynamo hub. I've had my Shimano dynamo hub for about 18 months now, and I've been very happy with it.
I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can spend the summer building up a wheel ready for the winter commute. Obviously I will need new lights and get the wiring right, but that is not the purpose of this post. When I took the nice shiny lump out of the box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
Hub dynamos do. It's as you move the coil from one magnet to the next. It feels very stiff when you've got the hub in your hands, but honestly it will vanish when the hub is in a wheel and rolling. You get as much pull forward to the next magnet as pull back to the last one, so there's very little net drag.
I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can spend the summer building up a wheel ready for the winter commute. Obviously I will need new lights and get the wiring right, but that is not the purpose of this post. When I took the nice shiny lump out of the box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
Is it likely that the cones are too tight and need to be slackened off a bit, I assume that the stepping sensation could be due to the magnets and rotors, but I would like to get confirmation that this is not a problem with the bearings.
In general with new hubs, it's common for cones to be over-tightened in the factory. You could be feeling this in addition to resistance from the dynamo.
I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can spend the summer building up a wheel ready for the winter commute. Obviously I will need new lights and get the wiring right, but that is not the purpose of this post. When I took the nice shiny lump out of the box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
I think this is the same model as mine, if it has the roller brake mount then it is the same.
When I took mine out of the box, I can remember thinking exactly the same thing, however I did not adjust the cones, and it has run perfectly for 18 months (minus bike/me downtime).
btw the wireing is very easy. I only use it to power the front lit.
I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can spend the summer building up a wheel ready for the winter commute. Obviously I will need new lights and get the wiring right, but that is not the purpose of this post. When I took the nice shiny lump out of the box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
I think this is the same model as mine, if it has the roller brake mount then it is the same.
When I took mine out of the box, I can remember thinking exactly the same thing, however I did not adjust the cones, and it has run perfectly for 18 months (minus bike/me downtime).
Yours may well be fine but, when in doubt, it's not a bad idea to check/readjust the cones to increase the chances of a hub running perfectly for 18 *years* (with the occasional service, of course).
I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can
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Quoted message said:
box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
This is normal with hub dynamos; the magnets and wiring have a series of preferred positions all the way round. The apparent effort doesn't affect you when riding - the other half of the time the hub is pushing itself forward into the next preferred position. -- David Damerell <[email hidden]> flcl? Today is Second Brieday, March.
I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can spend the summer building up a wheel ready for the winter commute. Obviously I will need new lights and get the wiring right, but that is not the purpose of this post. When I took the nice shiny lump out of the box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
I think this is the same model as mine, if it has the roller brake mount then it is the same.
When I took mine out of the box, I can remember thinking exactly the same thing, however I did not adjust the cones, and it has run perfectly for 18 months (minus bike/me downtime).
Yours may well be fine but, when in doubt, it's not a bad idea to check/readjust the cones to increase the chances of a hub running perfectly for 18 *years* (with the occasional service, of course).
IMHO it would be best if the OP builds the wheel before adjusting the cones to see how it feels built.
Don Whybrow said the following on 22/03/2007 20:36:
Quoted message said:
I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can spend the summer building up a wheel ready for the winter commute. Obviously I will need new lights and get the wiring right, but that is not the purpose of this post. When I took the nice shiny lump out of the box to admire, I couldn't resist having a little fiddle. It felt to me that it was taking too much effort to turn the hub on the axle and it felt like it was turning in steps.
I have a Shimano 3N71 dyno-hub, and that feels the same. You really don't notice the difference when riding.
Is it likely that the cones are too tight and need to be slackened off a bit, I assume that the stepping sensation could be due to the magnets and rotors, but I would like to get confirmation that this is not a problem with the bearings.
Thanks for all the responses, I will wait to see what it is like one I get the wheel built and had a spin with it.
-- Don Whybrow
Sequi Bonum Non Time
People must not do things for fun. We are not here for fun. There is no reference to fun in any Act of Parliament.
> I have just purchased a Shimano DH-3R40-QR Hub Dynamo so that I can
I think this is the same model as mine, if it has the roller brake mount then it is the same.
That's the one.
Do you have forks designed for roller brakes, or are you using the roller brake designed for disc mounts?
<Checks Shimano website ...>
I didn't know that there was any difference. The brake I have is the one that was fitted to the bike when I got it. It is the BR-IM75-F which appears to fit to disc mounts. Is there any significance?
-- Don Whybrow
Sequi Bonum Non Time
"I fought the Dharma, and the Dharma won." (Allen Ginsberg)
