The connector is supplied with mating half, but no pins. These are readily available from the USA, which to order 2 costs around £15 delivered. I couldn't find anything on the Yamaha site; they sell the normal hack adaptor with spade connectors to go direct onto the battery.
So, time to hack something together.
The pins started life as a cheap automotive pin crimp. Ampliversal ones are too well built to use. Remove the red cover, squash the hole a bit so that it fits the aperture in the mating half, the file a notch, and cut it to length. I did it at about 7mm, but try 9mm. Solder some wires on and push it in until it clicks. You're supposed to have waterproof ferrules too, but just push the original ones back in. Then mate.
You can get waterproof connectors on ebay, but I just used a standard 2.1mm barrel connector which I tuck back under the air intake. It's what I had on the old bike for 11 years and it never got wet or rusted. I've got a flying lead from the tank bag to a small 12/5V adapter. It's about 80% efficient, meaning the 12V x 2A = 24W from the bike can supply 24W / 5V * 0.8 = 3.8A@5V plenty for even the thirstiest products.
I then made the USB adapter.
I forgot to take pictures as I went, but the shot below gives you an idea
The pcb is a generic switching regulator, normally around 5 for £1 delivered. Takes up to 28V in and delivers up to 28V ish out.
I set it for 5.25V, as most branded USB adapters I've tried give out around this, or a bit higher. I had a spare USB socket, which I soldered to the PCB by flattening out the through hole tabs. Short the middle pins together to make it simulate a DCP (dedicated charging port - see https://www.maximintegrated.com/en/app-notes/index.mvp/id/4803 for a factual description of how to make your USB appliances draw more than 0.5A, or see pretty much any hobby site for rants abouts Apple's 'secret' wiring etc, etc) I did note in testing that my Samsung tablet would only take 1.2 - 1.4A with shorted pins, but would go to 1.51A with 300 + 100k resistors wired +5/0V to the shorted pins. It was fairly unscientific and for all I know it just needed less current at some times when it was charging. The official charger showed 1.8A. Life was too short to get too technical. All I want is a charger for the phone or GPS etc on the bike if I'm caught short.
The picture is taken during a soak test at around an amp. I say 'around' as the little meter thingy is about 10% accurate on amps, and 5% on volts.
A SMD LED next to the socket gives you power on indication with the plug removed. A piece of heat shrink finished it off. I didnt fit a fuse as the bike has a 2A.
Through the heat shrink, it feels like the chip is running at about 60C, which is pretty good considering there is no airflow. The chip, a MP1584, has a maximum dissipation of 2.5W, which IIRC gives a practical limit of around 5V/1.0A before the chip shuts down as the die hits 150C, assuming 14V in, 85% efficiency
5W out, 5.9W in = 14V@0.42A. Vd = 14-5 = 9V x .42 = 3.8W dissipated. Oops. Working that back for 2.5W gives 5V@0.66A
Perhaps I should have left the D+/D- floating to limit the draw to 0.5A
A soak test for an hour at 1A has been OK, so I guess the heat shrink is radiating a bit, plus the USB plug will be an external heatsink.
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