Dynamo Lights

@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