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Complete Your Profile- notoriouslev followed leds, homebrew, sensors, metalworking and 25 others channel 3 years ago
- notoriouslev commented on saullopez52's instructable How To Build A Bicycle Generator3 years ago
- notoriouslev favorited Flamethrowing Jack-O'-Lantern by randofo4 years ago

So I came up with a way to guesstimate the v-belt length you'll need to order for this project. It's pretty simple and should work with any sized bike. A quick note. You may want a bit more room for your generator, but mine is small enough that it fits nicely at the outer edges of the rim (see pic)Step 1: Measure the size of your bike's rear wheel. Mine (from rim to rim - not including the tire was 26" tall, which means I have a radius of 13". The equation to get the circumference of the rim is 2 x pie x radius = 2 x 3.14 x 13 = 81.64" around. Step 2: Subtract 1/4 of the circumference: 81.64 * 75% = 61.23Step 3: Add the diameter: 61.23 + 26 = 87.23" Long--------Optional Step 4: You can add extra length to the v belt in case you don't want the generator sitting just b...

see more »So I came up with a way to guesstimate the v-belt length you'll need to order for this project. It's pretty simple and should work with any sized bike. A quick note. You may want a bit more room for your generator, but mine is small enough that it fits nicely at the outer edges of the rim (see pic)Step 1: Measure the size of your bike's rear wheel. Mine (from rim to rim - not including the tire was 26" tall, which means I have a radius of 13". The equation to get the circumference of the rim is 2 x pie x radius = 2 x 3.14 x 13 = 81.64" around. Step 2: Subtract 1/4 of the circumference: 81.64 * 75% = 61.23Step 3: Add the diameter: 61.23 + 26 = 87.23" Long--------Optional Step 4: You can add extra length to the v belt in case you don't want the generator sitting just below the rear wheel's exterior. For instance to place the generator 1 foot behind the rear wheel, you add 12" for the extra distance behind the wheel, and then you use the Pythagorean theorem to get the additional v belt required to reach back to the tire: (12 x 12) + (13 x 13) ...then get the square root = 17.7". So to place the generator 1 ft behind the rear wheel of this bike, we add 29.7 inches to the 87.23" we already had and get 116.93"