Dynamo Lights

Which charge-through battery pack are you using? I had a look at Zendesk Zenpure whatever they were called but like my Anker batteries so got a larger one of them.

Maybe a switch inline with the D1 for faster riders?

I've the Goal Zero Flip 20. Works great, maybe the 10 version could be enough, but I could recharge the Edge 1000 at least 3 times before needing to re-charge the power-bank. Its not waterproof... I didn't care about that, they have the Venture 30 for that, but was too heavy for what I needed (just 1000km, not TCR/TransAm like you)

Yes the electrical switch is what I was thinking about, but didn't have time to do it myself before the 1000km brevet. Anyway at higher speeds there will be heatsink, but at least it won't get it when not being used. Heat wasn't a problem, I just were a bit careful before touching it.

Yes @acharnley I'll get the D1 fixed outside of the framebag (hopefully the new titanium model!), did it for the first 400km, but little rain came the first night and didn't care to get it fixed outside again for the rest of the ride. Both Garmin Edge 1000 and iPhone SE where complaining for Power Lost when riding at variable speeds, so I just wanted to do both things at the same time.... recharge power-bank and device.

I'm thinking of leaving my D1 on the aerobars - with the ports facing backwards it doesn't get too damp. Maybe fashion some kind of weather cap to cover the USB ports as a precaution.

I keep buying Anker batteries. Love them. But they're not waterproof and don't do charge-through. They're smaller than most other options and work really well but perhaps I should look at other options.

Pass-through charge is an obligatory feature in my opinion... so you don't have to care about how much charge gps/mobile/power-bank have... just leave it all connected, and only disconnect when you get to a climb that really hurts and don't want to think about the little watts you must be losing with the dynamo dragging.... or when night comes and lights should get all the dynamo power. A switch for those two moments would be awesome :), but disconnecting/connecting a usb cable is not so bad one-handed.

If it's raining though, I don't want it connected. I want it all safely packed in a bag with the weather cover over the USB port on my Garmin. My plan was to charge the battery during the day and then disconnect and use only the light at night with the battery alone powering the Garmin.

I've used a bit of home silicone sealant around the usb cable entry port of the garmin (with the cable connected), because it won't be leaving the bike (its also secured with a lanyard to avoid anyone trying to grab-and-run). Its easy to peel it off when the ride ends, and I don't have to plug again the usb cable into the Garmin under heavy rain (worst scenarios happen more often than they should)

As far as I know the D1 is waterproof, but @acharnley recommends that you don't let water sit too much on the usb connectors, just to avoid corrosion. So pointing the connector downwards would be enough for the rain (in my case the D1 was fixed to the frame with the velcro straps of the framebag, but pointed it upwards to made easier the connecting/disconnecting of the usb cables.

I also charged the power-bank during the day and used alone at night, but still there where some high-speed long descents at night when there was more than enough power for lights & D1. Just so you don't have to test it... supernova + D1 operating at the same time at night, in a 2-5% climb... you could see enough to ride without problems :D, but don't recommend it :)

Do you seal your hub connectors too?

How did you do it? With the given rubber sleeve that can be heated to make it tight? I just abused electrical tape over and over it, should invest some time in perfecting the electrical wiring :(

@hippy has indicated he's sitting at 30kph when the D1 gets hot. Admittedly the D1 was designed for touring cyclists and it gains about 15% more efficiency at slow/medium speeds due to the way the protection circuit is implemented. The alternative method I'd implemented previously in prototype units but it so rarely kicked in for touring cyclists (30kph for them is on a decent and pedalling) that it made more sense to go for higher efficiency and keep the protection for the odd occasion.

While the protection is well tested for touring cyclists I don't know how hot for how long it can go before failure (no failures so far and it does reportedly get very hot). There's a good chance for the titanium version the heat dissipation will be worse (thinner smaller case). For this reason sticky rubber mounts are included and instructions are clear to mount on the head tube facing forward.

So long as your D1 is outside the airflow at 30kph (or 10kph) will keep it fine. There are four solutions going forward;

1. install a switch and turn the D1 off when you know you're not charging a device and going fast.
   
2. I can continue my search for a different IC which accepts a higher voltage (I have done much research already and it doesn't seem possible without reducing efficiency and/or effectiveness at lower speed). This would allow me to move the protection trigger to a higher point.
   
3. I could do two versions, one for tourers one for fast riders like yourselves. The later would generate very little heat but would lose 15% efficiency at low/medium speed.
   
4. Always charge a device (although the D1 efficiency means the protection may still kick in, and it's likely if the device is already charged and not consuming power).
   
   

Re: USB port, don't allow water to sit in the port (angle it down). An alternative is to use a 30cm USB extension cable and tape the join to the D1 to waterproof it. The other end of the cable can become wet and is thus sacrificial - probably it'll need replacing in a year depending on how quickly the pins corrode - (note they corrode very quickly on micro USB)

http://www.ebay.co.uk/itm/0-3m-USB-2-0-High-Speed-Cable-EXTENSION-Lead-A-PLug-to-Socket-BLACK-008100-/262209230250

My average moving speed is between 25 and 29km/h on long distances (depends on how many mistakes I make, and if I'm going solo/group). The main group normally do around 19-22km/h trying to avoid the brevet time limit.

Two different models could be seen as a logistic problem for you, but it could be great to have a specific unit for touring/mountain biking (slower as you said) and another for "roadies" that average higher speeds, not just on descents. It would be another great reason to choose D1 above other market options... something specific is always better, unless you want to use it on different bikes for different rides

I suppose that integrating a button or a switch in the case would make it bigger, and also maybe not convenient for some unit placements, I'll think about a solution but this something like this could be great, to place it on the handlebar or frame.

I've used one of those USB extension cables too, because the power-bank doesn't have a cable, you must connect it to a female usb port, and it was a great solution.

I'm probably going to leave mine roughly where it is, on the aerobar extension and then use a couple of these short USB extension cables (http://www.ebay.co.uk/itm/400708565329) to be sacrificial as well as being flexible so a bit easier to plug stuff into rather than something fixed close to my armrests.

I carried out some further testing today (current titanium D1, but previous aluminium model very similar). 700c wheel size, speed by GPS.

No load

22kph - no heat
25kph - minor heat, few degrees extra
30kph - heating obvious at bottom of casing (where protection lives)

Charging Sony phone @ 470mA

22kph - no heat
25kph - no heat
30kph - minor difference I think, barely noticeable.

As long as the D1 lives outside the heat isn't significant, on the titanium one mounted on the head stock it cooled to ambient in 20 seconds (or so) after the speed came back down from 30kph at 60 seconds. I would not recommend putting the aluminium one inside a bag, it will insulate it.

What about descending speeds? Like 60kph

For how long? It is the combination of speed and time generating heat which must not exceed the density of the unit.

More heat will be generated ... but more airflow will dissipate it. The current model has a short cable to ensure users don't try to stick it in a bag. It's also on the installation card and on the FAQ. With no airflow, 60kph for an extended period of time - does not sound good.

I can not give a definitive statement that it will survive say 60kph for 2 minutes without a load. It was designed primarily for tourers which would need short term overvoltage protection.

I can say that to date there's been no failures with the electronics in any unit and that there's now quite a few audax roadies using them.

PS)

I recommend audax riders use SONDelux as these have a smaller generator more appropriate for these sort of speeds.

I'm using SP Dynamo, so does @hippy. I've made some descents over 60kph for 5 to 10 minutes... unit still works (but not sure a its 100% :D) but charges stuff.

Hope to see someone making an unit for non-tourers that do TCR / TransAm / Tour Divide / etc...

It's fine then, its performance won't degrade. If the protection were to fail it would destroy the converter and you would have no output.

60kph for 5 to 10 minutes is crazy! :)

Was that when it was in your bag as well?

Seems the weather on the Scottish ride was a lot like this.

http://youtu.be/TfbaZUtiL0o

I touched mine (ooo nurse) after a few longer descents and it seemed ok most of TCR. I'll be leaving it under the aerobars where it's cooled and quite handy for plugging stuff in.

I'm thinking about going for a pair of dynamo lights on an old 26" MTB - I'm looking for a fairly budget solution, just how terrible are the Shimano DH-3N31 hubs? From what I can tell they are fairly notchy... Is there another budget option to consider when going for hub dynamos? Is there a particular hub that's well known for price against performance?
This bike won't be really heavily used - mainly used on shitty days.

I'm a complete novice to this so any advice would be appreciated!

I think those are what are on the public hire scheme bikes up here in Glasgow.

I reckon the notchiness is about as noticeable as on the Alfine hub I have, which is to say, not in the slightest bit noticeable!

There's an ebay shop who sell dyno wheels all built, bundles with lights too, really fast and easy and cheap. Bought the basic lights & 26 wheel for a present, has a pretty basic shimano hub but it's fine. They do B&M setups as well. Can't remember the name but it's been talked about here or on the dynamo hubs thread by @cornelius_blackfoot amongst others.

Edit: Shop name is partsforbike-online.

@M_V Thanks, good to know

The bundles they do look good, but the light sets that come don't suit my needs -
So if I was to go for a wheel like this:

Then I'd need any light set that worked on a 6v right?

Then I'd need any light set that worked on a 6v right?

Pretty much.

I bought my lights from Rose, spent a bit on the front (£40 ish I think?) and glad I did as the light is fantastic. It's the IQ Cyo something or other. rear light I just went for a dirt cheap B&M number and again, it's fantastic. Think it was about £7 and it's super bright.

Probably worth chucking a few extra connectors and shrink wraps etc into your order too.

I've just bought a bottle dynamo to fit to my shopper/beater/deep winter commuter bike. Need lights now.

Lights for a bottle dynamo are different to those for a hub dynamo yeah?

Edit: There are sets (inc a bottle dynamo but the one I've bought is a bit nicer so will be using that) on ebay for £9. Given that bottle dynamos will be relatively inefficient compared to a hub dynamo, is there much to be gained by spending more than this on lights for it?