3D-printed Electric OFO Bike Mod

thingiverse

Hi, rental bikes such as OFO are a great way to get around the city but they often don't support multiple gear speeds. Here's a DIY 3D-printed mod that can convert any OFO bike into an electric-assist system in just two to three minutes. You'll need to attach the DIY controller and the DIY friction-drive unit to the bike, and you're good to go. Below are the parts needed for this project. Friction Drive Unit: * 4 Ikea standard L-brackets for anti-topple * M10 60mm bolt with nut * M4 30mm screws x 2 * M4 25mm screws x 2 * M4 15mm screws x 6 * M4 10mm screws x 2 * M4 washers x 14 * M4 nuts x 18 * M8 nuts x 6 * M8 washers x 2 * 75mm-wide hinge with 6 self-tapping screws Steel Extension spring 39.7mm(L) by 11mm(OD) by 1.6mm (111N per mm) M8 90mm threaded rod 608z bearing (optional) Turnigy Skateboard Conversion Kit Spare Parts - Motor Mount Flat Head Stainless Steel Knurled Nuts M8 x 2 8044 Timing Belt Pulley Wheel DIY Single Motor Mount Bracket for 5065 16T Motor Pulley Head Stainless Steel Knurled Nuts M8 x 1 HTD3M belt 252mm by 1.5mm Motor: * KEDA 63-64 190KV Brushless Outrunner 10S 2000W ESC: * Hobbyking Opto 90A 7S 3D-printed mount for Friction Drive unit: Included in zip file Lipo: * 6S 5500mah x 2 (use in parallel) Wires and Plugs: * 2m 12AWG red and black wires * XT60 plug male or HXT4mm connector * 2m 26AWG servo wires * Servo plug male Spring-loaded-Lever Throttle Controller: * Cheap servo tester with knob and 3-position switch * Standard-size 20kohm potentiometer * 3mm by 20mm extension spring x 2 * 180 2GT timer belt * M3 30mm screws x 2 * M3 10mm screws x 2 * M3 threaded spacer 10mm for micro quadcopter x 2 * M3 4mm-OD bearings x 4 * M2 8mm self-tapping screw x 4 3D-printed Throttle Controller parts: https://www.thingiverse.com/thing:2905472 Throttle Controller Mounting brackets: * M4 40mm bolt and nut x 3 * M4 washers x 6 3D-printed Mounting brackets (AKA 'Go-Pro Mount'): https://www.thingiverse.com/thing:86238 Rocker switch for emergency-stop Tools and misc: * Black tape, heat shrinks, Red Loctite, Zip ties, hotglue gun, superglue * 60w soldering iron, solder and flux, hand-crank drill and drill bits (3mm, 4mm and 5mm), hammer, hand-held electric rotary tool with grinding disc, some cling-wrap plastic to protect motor magnets from metal dust