10W dynamo with charging ports

[mrcharly-YHT]

https://www.kickstarter.com/projects/1595966801/ep-charger/comments

I think the design is doubly-flawed - on-tyre will slip in wet weather and the charging ports are USB which are not robust in the wet either. But then the designer is from Perth, WA, which either has torrential rain or non at all, so I'm guessing he doesn't ride in the rain.

[Torslanda]

Dog knows what the drag will be like. 3w feels significant in a bottle dynamo and you can't get something for nothing...

The video does show that it works immersed thobut.

[mrcharly-YHT]

The video does show that it works immersed thobut.

That's for a brief period. My wired cycle computer works for a while in the rain, then it starts to fail. Loads of people here have had probs with standard USB connectors in the rain, its just the connectors not working once dirty water gets in there. Working submersed in clean tap water is one thing, working when a bit of salty sweat has been washed in is another.

He doesn't show a test with wet tyres and I don't think those smooth rubber bands will grip a wet tyre. Won't work too well with mudguards either!

[Cudzoziemiec]

I saw the tyre comments and expected something like the old bottom bracket dynamos that ran off the tyre tread but it's effectively two bottle dynamos opposite each other. Perhaps that layout increases grip by squeezing from both sides? I do seem to remember Nutty once otp using two bottle dynamos in his quest for moahr light, but I think his were one in front of the other.

[sojournermike]

What we probably need is something that outputs  nothing on climbs, 3 watts on the flat and 10 watts plus on descents. I'd still prefer to build the electromechanical bits into a hub though.

Should be possible with current tech.

[Greenbank]

https://www.kickstarter.com/projects/1595966801/ep-charger/comments

I think the design is doubly-flawed - on-tyre will slip in wet weather and the charging ports are USB which are not robust in the wet either. But then the designer is from Perth, WA, which either has torrential rain or non at all, so I'm guessing he doesn't ride in the rain.

There have been favourable reports of the Velological rim dynamo (http://www.velogical-engineering.com/velogical-rim-dynamo---standard-bicycle-dynamo---smooth-running.-lightweight-efficient) even in wet weather. Modern 'sticky' materials are a whole lot better than the old bottle dynamos that used to run on the bumpy sidewall treads.

The placement of the ports, and the main block itself, on that EP-Charger does look awful, but it's probably a prototype.

I understand that the electronics bit needs to be out in the airflow to shed heat from the rectifier, so stuffing it in a bag isn't a good idea, but that doesn't mean the USB ports need to be exposed. What I want (and the same goes for things like the B&M Luxos U) is that instead of a USB socket on the device it has a USB socket/sockets at the end of a 30cm cable. That way I can easily protect them from water (even just in a small top tube bag). The Luxos U (last time I checked) has the USB socket on the light switch, which means it is still exposed, or you have to bury the light switch in the bag and lose that functionality.

The Igaro D1 (https://www.igaro.com/) is getting there, I'd want a longer cable to the USB socket though.

[mrcharly-YHT]

The Velological runs on the rim (which is less likely to be constantly wet) and very sensibly makes use of O rings (which are easy to source and replace).Running on the hard smooth surface of the rim is going to keep rolling resistance down as well.

The EP runs on the tyre, and on the tread part of the tyre, which will be constantly wet in wet weather. I think that is a major design flaw.

[Kim]

What we probably need is something that outputs  nothing on climbs, 3 watts on the flat and 10 watts plus on descents. I'd still prefer to build the electromechanical bits into a hub though.

Should be possible with current tech.

I think that's called a hub dynamo.

[Dave_C]

I think someone needs to invent a wireless charging system which fastens together with magnets, like Apple's system, only contactless so no exposed metal can corrode.

[Greenbank]

I think someone needs to invent a wireless charging system which fastens together with magnets, like Apple's system, only contactless so no exposed metal can corrode.

http://www.cyclingabout.com/magnetic-dyna-snap-dynamo-cable-connectors/ is as close as you can get without it being wireless...

[sojournermike]

What we probably need is something that outputs  nothing on climbs, 3 watts on the flat and 10 watts plus on descents. I'd still prefer to build the electromechanical bits into a hub though.

Should be possible with current tech.

I think that's called a hub dynamo.

[Mr Larrington]

I saw the tyre comments and expected something like the old bottom bracket dynamos that ran off the tyre tread but it's effectively two bottle dynamos opposite each other. Perhaps that layout increases grip by squeezing from both sides? I do seem to remember Nutty once otp using two bottle dynamos in his quest for moahr light, but I think his were one in front of the other.

I've got a brace of Lightspin bottle dynamos on my Trice, but arranged one either side of the rear wheel.

[zigzag]

i quite like the idea, although the use cases need to be considered.
1. for touring - how will it work with the tyres that have some knobbles on they shoulders, how will the dynamos deal with mud and gravel that is stuck to the tyres?
2. for commuting / leisure / utility cycling - are those rides long enough to require such on-board charging system?
3. for fast riding, i.e. adventure racing / audax - how much drag are those dynamos creating, would the riding still be enjoyable?

[trekker12]

I understand that the electronics bit needs to be out in the airflow to shed heat from the rectifier, so stuffing it in a bag isn't a good idea, but that doesn't mean the USB ports need to be exposed. What I want (and the same goes for things like the B&M Luxos U) is that instead of a USB socket on the device it has a USB socket/sockets at the end of a 30cm cable. That way I can easily protect them from water (even just in a small top tube bag). The Luxos U (last time I checked) has the USB socket on the light switch, which means it is still exposed, or you have to bury the light switch in the bag and lose that functionality.

The latest Luxos U I've just bought now has a cable hard wired into the light switch with a female USB on the end - it's only about 4 inches long though so you can hide it in a handlebar bag but it's not long enough to reach to a top tube bag. I'm looking at adding a piece of heatshrink to cover the exposed bit of the USB and an extender cable I'll try not to interfere with too often. Not ideal but a bit better.

[Greenbank]

Thanks, looking online (http://en.bumm.de/produkte/dynamo-scheinwerfer/lumotec-iq2-luxos.html) I see the latest latest version has the female USB socket on a separate cable connected to a fly lead from the light switch, so there might be an extension cable or a longer USB fly lead available at some point...

[andrew_s]

The conector between the USB port and the light switch looks t be the same as is used on the eWerk, so extension cables are available, or direct micro/mini USB plugs

[Ian H]

I've got a brace of Lightspin bottle dynamos on my Trice, but arranged one either side of the rear wheel.

Have you tried them with LED lights?  I still have one (on E's bike) but running halogen, which is gives a gloomy yellow pool of light compared to LED.   My concern is about the Lightspin's internal electronics v LED wizardry.

[Mr Larrington]

I've got a brace of Lightspin bottle dynamos on my Trice, but arranged one either side of the rear wheel.

Have you tried them with LED lights?  I still have one (on E's bike) but running halogen, which is gives a gloomy yellow pool of light compared to LED.   My concern is about the Lightspin's internal electronics v LED wizardry.

I think the light on the thing are fairly old-skool LED ones but I'm pretty sure that the modern breed would have indigestion if fed the Lightspin's particular variety of voles.  Even back then they wouldn't work with a Solidlight.