Velological Rim dynamo

[nobby]

Any opinions on this dynamo and suitable headlamps or a link to a previous discussion that I have been unable to find, please?

[De Sisti]

Have a gander at the following to help you form an opinion.

http://www.elessarbicycle.it/velogical-dynamo-review/

http://www.velogical-engineering.com/velogical-rim-dynamo---standard-bicycle-dynamo---smooth-running-lightweight-efficient?gclid=EAIaIQobChMIr6KrnsfI2wIV5b3tCh2YyQEzEAAYASAAEgLq9_D_BwE

https://www.bikeforums.net/electronics-lighting-gadgets/922447-velogical-rim-dynamo-schmidt-edelux-ii-combination.html

[nobby]

Have a gander at the following to help you form an opinion.

http://www.elessarbicycle.it/velogical-dynamo-review/

http://www.velogical-engineering.com/velogical-rim-dynamo---standard-bicycle-dynamo---smooth-running-lightweight-efficient?gclid=EAIaIQobChMIr6KrnsfI2wIV5b3tCh2YyQEzEAAYASAAEgLq9_D_BwE

https://www.bikeforums.net/electronics-lighting-gadgets/922447-velogical-rim-dynamo-schmidt-edelux-ii-combination.html

Thank you. That is very helpful.

[rogerzilla]

I can't work out whether it's really only 1.5W or whether that's just the new German regs forcing many dynamos to be labelled at 1.5W rather than 3W because they can't give 3W at Granny Schmidt's town bike speed.  One review suggested only 2 of 4 LEDs lit up on their lamp but, as we know, many bike equipment reviews are made up in an office.

[Samuel D]

Yeah, I’d also like to see an output curve for this dynamo, not that I’m likely to buy it while good hub dynamos are so cheap. I just bought a Shutter Precision SV-9 that is labelled 1.5 W. Reviews suggest its output is similar to my departed SONdelux that developed practically full brightness with a Cyo Premium at about 25 km/h. At 15 km/h it was already plenty to see with at that speed. How much power do you need with LED lamps?

[nobby]

Thank you all for the advice.

I only rarely ride in the dark and have relied on a Fenix LD20 torch up to now.
It has worked fine, but this little dynamo seems good if I do not want  to have a hub dynamo built into a wheel.
Cheers

[fd3]

I wonder whether this will be the start of a new trend.  A really good bottle dynamo has a lot going for it and would make new wheels much cheaper.  It might be a bit like the solidlights when they first came out - novel and excellent, but soon surpassed once big hitters (like B&M) joined the party.

[Nick H.]

It has 3 versions. AFAICS they all have the same output but they start working at different speeds. What's the point? Why not have just the one version?

[Kim]

It has 3 versions. AFAICS they all have the same output but they start working at different speeds. What's the point? Why not have just the one version?

For different sized wheels, presumably, as you do with hub dyanmos.  Sorry, brain-fade due to heat and prolonged exposure to perl.  Unlike a hub dyanmo where the wheel turns at different speeds depending on its size, the rim will always move past at slightly less than ground speed.

I can see the appeal of a "loads of output at low speeds" model for things like lighting on cargo trikes or charging batteries on a touring cycle, vs a regular StVZO specification model for lower resistance.  Three different versions seems excessive.

[fd3]

Because you're an engineer and you can.  (and you don't have someone in marketing to help you out).

[Paul H]

It has 3 versions. AFAICS they all have the same output but they start working at different speeds. What's the point? Why not have just the one version?

Resistance? Before LEDs and hub redesigns, faster riders were using hub dynamos designed for smaller wheels for that reason, lower resistance at the cost of slow speed output.  I'm not sure if I could tell the difference, but some can and for others just knowing that's the case is enough to put them off.

[andrew_s]

It has 3 versions. AFAICS they all have the same output but they start working at different speeds. What's the point? Why not have just the one version?

I'd suspect that the power generated doesn't tail off with increased speed in the same way as a hub dynamo does, and that if you use the "lots of power at low speed" version with something that will accept lots of power, like a big battery pack, and ride fast, you'll overcome the traction between driving wheel and rim, and end up getting not a lot, as well as damaging the traction o-ring.

[Frank9755]

This isn't what users report. 
It has been used successfully on TCR and IndyPac.  It seems to be a well-engineeered and reliable piece of kit.
I looked into getting one last year but it wasn't compatible with my preferred charging setup so just stuck with batteries.

[andrew_s]

Would IndyPac or TCR riders have selected the low speed version?

[Frank9755]

I spoke to velogical and they advised either Special or Touring.  Not the Sport version as it has a low voltage so would be harder to power gadgets.
There are more issues to do with peeing gadgets than with hubs but I didn't remember all the detail after I decided not to go down that route.
I have to say they it still think it's a super little gadget and would get one of I could think of an excuse!

[igauk]

I've been tempted by this as an alternative to getting a hub dynamo wheel built up. What has prevented me from ordering one is a) the noise - which seems to vary between 'can't hear it over the wind' to 'banshee wail' according to reports, I think a lot depends on how parallel to the rim you get it b) potential difficulty on installing it on the front wheel of a Moulton (back wheel would be fine, but I don't like trailing wires along the length of a bike, especially when it would only be powering a front light c) for €150 I could get a SP hub front wheel built and I don't swap wheels/bikes etc. In the plus column this leaves it's lighter (the Moulton's a boat anchor so not really an advantage) less drag when it isn't being used (but I don't think dyno hub drag is that much of a problem). I'm still tempted just because it's a a cool bit of engineering and it would fit with the Moulton's over-engineered solution that gives marginal gains ethos.

[Samuel D]

[…] less drag when it isn't being used […]

True at very low speeds (but does the tiny drag at those speeds matter?), but at common speeds the aerodynamic drag of this wart on the bicycle would probably offset the lower drag of a regular front hub versus a dynamo hub – at least for low-drag dynamo hubs like the SONdelux.

[igauk]

[…] less drag when it isn't being used […]

True at very low speeds (but does the tiny drag at those speeds matter?), but at common speeds the aerodynamic drag of this wart on the bicycle would probably offset the lower drag of a regular front hub versus a dynamo hub – at least for low-drag dynamo hubs like the SONdelux.

The whole frame of a Moulton is an aerodynamic 'wart'! Lower frontal area, but after that turbulence city...

[Nick H.]

I spoke to velogical and they advised either Special or Touring.  Not the Sport version as it has a low voltage so would be harder to power gadgets.
There are more issues to do with peeing gadgets than with hubs but I didn't remember all the detail after I decided not to go down that route.
I have to say they it still think it's a super little gadget and would get one of I could think of an excuse!

Do you know your way around the specs on their site? I couldn't see any difference between the versions except the speed at which they start to generate. But from what you say there must be a lot more to it than that. What are the voltages of the different versions? And do you know how one would calculate the time taken to charge a particular gadget? Is there a formula one could use? I wish I understood it better...but I failed my physics O level.

[Frank9755]

I researched it 18 months ago but, after I decided not to buy, I've forgotten most of it so, no, not really!

[Phil W]

The trekking will generate roughly 8% more power than the sport model at the same speed. The special will generate roughly 20% more power than the sport model at the same speed.  So a bit like choosing between a Son Deluxe or a Son 28, depends mostly on your charging needs beyond the lighting.

I did briefly look at these for hew bike build but the whining on the you tube vids put me off.

[Nick H.]

Me too. The reviews say it's quiet but the youtube vids can't all be wrong.