This is an updated version of my original Bike Generator. The first version served its purpose but was fairly limited. BikeGen, is better in almost every way and here are some of the reasons why:
1. The generator motor is now mounted with more rigidity to the rack instead of the frame.
2. The friction drive wheel is mounted to the motor with a clamping coupler and now runs on the braking surface of the wheel and not directly on the tire.
3. BikeGen recharges two AA batteries instead of powering the headlight directly, so the lights stay on even while your stopped.
4. Two AA batteries are used to power both the head light and the tail light, which means I don't have to bother buying AAA batteries for the tail light.
NOTE:Please read my Bike Generator Instructable and follow the steps about building the the circuit board before attempting to build BikeGen.
Step 1: Get the Tools
Tools You Need to Have
Step 2: Get the Materials
Aluminum Angle 3/4"x3/4"-1/16"thick
Aluminum Angle 1-1/4"x1-1/4"-1/16"thick
4 - #6-32 nylon-lock Nuts
2 - #6-32 x 1-1/2" long Machine Srews
2 - Springs
2 - 1/2" #4-40 Stand-offs
4- #4-40 x 1/4"long Machine Screws
2- #4-40 Nuts
18 gauge wire - roughly 25ft
2 - DPDT switches
12volt car outlet
2200 ohm resistor
Battery Holder for 2 AA batteries
Everything used to make the Bike Generator
Other Needed Items
Small Plastic Organizer Box
Step 3: Make the Generator Motor Mount
The 3/4" aluminum angle was made to mount to the motor The 1-1/4" aluminum was made to mount to the rack. These two parts are connected together by the two #6-32 machine screws and the two spring. The screws thread into the tapped holes on the motor mount with the springs around them. This allows for the motor to move with the rim as you ride. This ensures that the generator wheel is always in contact with rim. The #6-32 all-thread was used to make two U-bolts. They fit the size of the bars on the rack.
I have included two drawings in the pdf for the two brackets I made to mount the motor. I also created an assembly drawing of the motor, wheel, and brackets. You will need to download the freeeDrawings Viewer to view the drawing.
Step 4: Wire the Electronics
The variable voltage regulator needs to be set up to output roughly 12 volts. Here is all the information you'll need on the voltage regulator LM317 Voltage Calculator I chose to shoot for 13.75volts, because I have measured the power outlet in my car and its usually over 12 volts. Also I could reuse the 220ohm resistor for 13.75volts. The original 220ohm resistor needs to be desoldered and then placed in the same location as the 150ohm resistor. The 2200ohm resistor can then be soldered in the place of the 220ohm resistor. I then used a dremel to spin the motor to make sure the regulator was working right. It output 13.88volts which was right on the money.
So the original Bike Generator circuit will rectify the AC power from the motor and regulate the voltage to 13.75volts. That power will then be fed to the charger circuit. The charger is then connected to a DPDT switch which is used to switch the batteries form the charger to the lights.
Step 5: Mount Everything to Your Bike
Once everything is connected mount it all to your bike and your ready to go.