During university I had issues with biking to school and being really sweaty on arrival. An electric bike was something I was really interested in, but the options available to modify my bike (HUB motor or Bafang mid-drive kit) didn't seem like the options I wanted to go with (due to them compromising the quality of the components they replaced like the wheel or bottom bracket).https://ift.tt/2N5s7vF modeled my frame in Solidworks and did research to find a motor that had the envelop dimensions I wanted with an appropriate output rpm as well. electricscooterparts.com had a DC motor that fit the requirements with an output rpm of 400 rpm. Coupling a freewheel hub on the motor's output shaft allowed the pedals to be spun without turning over the motor. The speed is reduced from the motor to the chainring (13t to 50t), with a theoretical max rpm of 104 rpm. This is on the high end of what is comfortable to pedal at, which was preferred over being too low.Initially I 3D printed the components to check the motor's location and chain alignment. After verifying everything, adjustments were made to the mounting apparatus so it could be easily machined with a 3-axis CNC and manual lathe. I machined all the parts out of aluminum.The battery and cycle analyst V3 were purchased from Grin Cycles, which allows the bike to be limited to 32km/h and 500W (legal in Canada). The bike has already gone hundreds of km with no reservations (max power hill climbing etc.). The maximum range is approximately 75 km with a continuous power output between 150-300W.Album Link:https://ift.tt/2tK4UpN via /r/DIY https://ift.tt/2N4L0yM
