How to make an effective bicycle generator:
- Amp Meter
- Put an amp meter (from a car or another source) in series with the alternator. This allows the person pedaling to see how much output is produced.
- Front Wheel
- Take the front wheel (tire, rim and spokes assembly) off and mount the remaining yoke on a stable platform made of wood. Use the same bolt holes that held the wheel on.
- Rear Wheel
- Raise the rear wheel about 1"-2" above the platform so that the rear wheel turns freely. Bolt this to the frame of the bike about 3"-6" in front of the back axle. This allows 2 support pipes on each side to bolt or strap it to. Could use 2" x 4" wood for the front and back supports. Use triangle supports cut from plywood or any other wood to make it stable (side to side motion). If needed carefully cut a notch in the back right wood support, so that the chain, and cables have plenty of clearance.
- Purchase a V-belt or V-ribbed belt big enough to go over the alternator and back rim. I have found it easier to find the Serpentine or 5, 6, or 8 V-ribbed flat belts in the lengths needed. A 5 ribbed belt is 45/64" wide. A 6 ribbed belt is 27/32" wide. A 8 ribbed belt is 1" and 1/8" wide. These are more expensive and cost about twice as much as the 11MM or 15MM wide single V-belts. However, they should last longer and will transfer more power. Also the alternators that use these have smaller diameter pulleys. Which is an advantage. Flat belts should work better on the bare bicycle rim. They would be less likely to turn over.
- The alternators that use flat belts are more expensive, deliver more amperage and typically have an internal voltage regulator. The older alternators have the voltage regulator separate and are a lot less to purchase. Typically local rebuilt prices are estimated to be $20-$40 for the older 60 amp (Ford, GM in the 1970's) type and $110 to $170 for the newer 70 amp and higher amperage. All of these types from time to time can be picked up at yard or garage sales.
- Mount the alternator on a peace of wood that is hinged (door hinge) to the platform (plywood, plank, etc.). This would be behind the back wheel. The weight of the alternator helps to give it belt tension. A spring could be attached to add more belt tension if needed.
The result would take no welding, and no great modification of the bicycle, so that if you wanted to unbolt it and put the back tire and front wheel back on you could still ride the bike. It does take wood and a long enough belt.
Offered by Mike.