This is my bike light that uses a GU5.3/MR16 12v LED spotlight and a cheap Li-po.
I wanted a decent amount of light for cycling on dark cycle paths and figured I could use a 12v LED spot and some spare Li-po packs.
You will need:
1 x GU5.3/MR16 12v LED Spot (available for not much money from DIY stores - I found a 4.8w 350 lumen one from Sainsburys for just over a quid)
1 x GU5.3/MR16 wire socket (ebay/maplin etc)
1 x Battery - I leave that choice up to you, but I am using a spare Turnigy 7.4v 2 cell 1Ah Li-po. Initial tests are encouraging with this pack lasting over 2hrs.
Some wire, sockets, heat shrink etc - Again the choice is up to you. Use what you have handy. Wireup the led to suit.
Some M4 nuts and bolts.
1 x Light Body
1 x Light Rim (Optional)
1 x Mount Arm (Note: I've not tested the arm as the light body fits in place of the front reflector and uses that arm)
The LED was a really tight fit and I had to scrape some plastic off the edge of the led and the housing. I've added some extra clearance to the model but needs testing.
I glued the led in place with super glue followed by the light rim and more super glue around the edge. Time will tell if it can stand the knocks and bumps.
Fit the light to the mounting arm and fit to bike!