Making a 12V bulb work in a 6V socket

12v-led-in-6v-socket

This is something of a square peg in a round hole type of problem. [Kiel Lydestad] has been riding a vintage Moped around. You know, a motorcycle that can be pedaled like a bike. He of course wants to keep the thing looking stock, but also needs it to be fully functional. Enter this light bulb replacement project. His brake light needed a new bulb, and he managed to make this 12V LED bulb work in the 6V socket.

An LED is a really great choice for this application since the Motobécane Moped uses a magneto generator to power the lights. It won’t pull much current, but it did need modification to run from half as much voltage. [Kiel] mentions that it may have been possible to crack open the LED tower and adjust the current limiting circuit inside, but he felt it was easier to just add this voltage doubling circuit. He assembled the components in a way that still allows them to fit in the metal base of the bulb.

Home brew motorized bicycle is a super grocery getter

[Thor] sent in an awesome motorized bike build he found coming from the fruitful workshop of [Jim Gallant]. It’s an incredible piece of work built nearly entirely from scratch.

[Jim] welded the frame together on a home-built jig that keeps all the chrome-moly tubes in alignment before they’re pieced together. With the jig, the frame was kept extremely straight making a bike that turns very well and can be ridden no-handed.

All of [Jim]‘s previous motorized bikes used small Honda engines, but after hearing Robin Subaru engines are more reliable he decided to give one a go. The motor is attached to the derailleur gears with a continuously variable transmission usually found in scooters. [Jim]‘s earlier motorized bikes didn’t have indexed shifting and disc brakes like modern motorized bikes, but he decided to throw them in anyway. Everyone who rides his new super grocery getter comments on how smooth the ride is with these additions.

While [Jim] doesn’t have an official speed or MPG rating, he’s guessing this bike can carry three bags of groceries at 30 mph at 170 miles per gallon. A very efficient mode of transportation that is much safer than the other motorized bikes we’ve seen before.