Non Hub Dynamos

[drossall]

Maybe it was. I was so accustomed to running them on the tyre that it never occurred to me to try. But I had problems with the rubber ring slipping, and always replaced them with the knurled metal wheel, which did run properly on the tyre.

Could be that the ring would have been OK on a rim.

[tatanab]

I was using a Nordlicht with a rubber ring (as supplied from new) on the tyre with no slippage issues.  I suppose it might depend on whether you had the dynamo leading or trailing the fork leg.  I still have a rubber ring in my box of bits if anybody needs one.   My Nordlicht came with an optional roller that was like a wire brush.  I never tried it, but I think it may have been for use in snow.

In the days before Nordlicht, it was common practice to put a rubber ring/grommet on the roller.  Seldom a problem with slippage.  It may also have been to reduce the RPM of the dynamo to protect fragile bulbs at highish speeds.

[drossall]

I suppose it might depend on whether you had the dynamo leading or trailing the fork leg.

Surely you could get left- and right-handed ones to deal with that?

[andrew_s]

There are two modern rim dynamos.

They have the same problem that previous high efficiency sidewall dynamos have had (Lightspin, B+M S6): they are as expensive as hub dynamos.

[jsabine]

There are two modern rim dynamos.

They have the same problem that previous high efficiency sidewall dynamos have had (Lightspin, B+M S6): they are as expensive as hub dynamos.

But they don't need a wheel build.

[Frank9755]

There are two modern rim dynamos.

They have the same problem that previous high efficiency sidewall dynamos have had (Lightspin, B+M S6): they are as expensive as hub dynamos.

More expensive, if you don't include the wheel build, but a potentially superior product as you can turn them off completely, which you can't do with a hub dynamo.  However, what I've heard from a Velogical is that they are still a bit noisy to be pleasant to use.

[rogerzilla]

There are two modern rim dynamos.

They have the same problem that previous high efficiency sidewall dynamos have had (Lightspin, B+M S6): they are as expensive as hub dynamos.

But they don't need a wheel build.

At least you can offset the weight against the front hub you've replaced.

[Tommyp27]

Thanks for all the advice on this. Looks like it will be a hub dynamo, since the decent non hub ones cost as much as getting the shimano built into a decent wheel and a half decent light.

[Kim]

There is another one, called Pedalcell.  See here for article on them:

https://www.cyclingabout.com/rim-dynamos-can-now-generate-more-power-than-hub-dynamos/

Best avoid that one:

Internals of generator cheaply made, it disintegrates if you go too fast (documents say not to go over 40mph).

<a href="http://www.youtube.com/v/o7xfGuRaq94&rel=1" target="_blank">http://www.youtube.com/v/o7xfGuRaq94&rel=1</a>
https://youtu.be/o7xfGuRaq94

The Rule According To Kim™ about adhesives would appear to apply...

[Frank9755]

Thanks for flagging.  I didn't buy one - although I am a sucker for novel kit. 
I could have done with a TLDR for that video!

[Russell]

I wonder if the Sunup spoke dynamo still available.  Had mine for years and it's very good.

Just looked,.Yes, but Spinup now

https://www.spinup.life/

Prices, at a quick glance, go from 'king hell that's expensive to that's not bad really.

[mzjo]

I wonder if the Sunup spoke dynamo still available.  Had mine for years and it's very good.

Just looked,.Yes, but Spinup now

https://www.spinup.life/

Prices, at a quick glance, go from 'king hell that's expensive to that's not bad really.

At the other end of the scale I still have a couple of "New Watson" sidewall dynamos off bicyclettes that appear to work fine (although that's just generating while I spin them by hand, I haven't actually mounted them to use in real life); they must be getting on for 70 years old and the first bit to fail will undoubtedly be the spring and mechanism that holds them against the tyre!

[mrcharly-YHT]

Thanks for flagging.  I didn't buy one - although I am a sucker for novel kit. 
I could have done with a TLDR for that video!

TLDV for other people

Internals of generator cheaply made, it disintegrates if you go too fast (documents say not to go over 40mph).

[Frank9755]

Thanks. So don't go down hill with it, basically!

[Frank9755]

I wonder if the Sunup spoke dynamo still available.  Had mine for years and it's very good.

Just looked,.Yes, but Spinup now

https://www.spinup.life/

Prices, at a quick glance, go from 'king hell that's expensive to that's not bad really.

Thanks for posting - not come across that before.  Looks interesting, although  the website doesn't explain how it works very well. 
Can you switch it on and off - or would you have to patially uninstall it?

EDIT - looking at the installation instructions, it looks like you would have to take it off to get it to stop.  So less interesting (for me)

[Russell]

I wonder if the Sunup spoke dynamo still available.  Had mine for years and it's very good.

Just looked,.Yes, but Spinup now

https://www.spinup.life/

Prices, at a quick glance, go from 'king hell that's expensive to that's not bad really.

Thanks for posting - not come across that before.  Looks interesting, although  the website doesn't explain how it works very well. 
Can you switch it on and off - or would you have to patially uninstall it?

EDIT - looking at the installation instructions, it looks like you would have to take it off to get it to stop.  So less interesting (for me)

I suppose in effect it's like a hub dynamo in that it's always turning.  I have had one for many years and I don't notice it with the light on and certainly don't with the light off.  Lift the back wheel up and give the pedals a sharp shove and the wheel will spin for quite a long time.  Maybe a pro wouldn't have one but an audax rider would not be aware it's fitted ay more than he would by having a SON in the front wheel.

It's main advantage is that it's 3 phase, so definately not a dynamo!, whereas other generators are single phase.  That increases the low speed power.

If you're in the SE come and look at mine.

[Russell]

Just tried spinning the back wheel using a gentle shove on the pedals, 15 secs to standstill with lights on, 45 secs lights off.  Tried similar on tandem at it spun for 51 secs.  Different wheel size, different tyre size but no dynamo so doesn't tell us much except drag with lights off is of a similar order to no dynamo.