583 circuitsmiths electric power assist bicycle

The decision to use electric power was made due to its quieter operation, lack of odor, and ease of carrying the bike up a flight of stairs. The selected conversion kit is manufactured by Currie. Although factory service is lacking, EVdeals is a knowledgeable dealer. The motor provides over ½ horsepower (600W), which is sufficient for a bicycle. Assistance is limited to approximately 20 mph, but there is ample midrange torque. The rear wheel is driven through an adapter that connects to the rear hub. Modifications were necessary from the outset as the kit was not designed for the thicker frame tubes of an aluminum Cannondale touring bike; it is primarily intended for steel frame mountain and hybrid bikes. Notches were ground into the drive plate that houses the motor, gears, and chain. The battery mount was also modified, and a voltmeter was added that indicates half the actual voltage for better readability. The throttle was mounted upside-down on the drop handlebars. A heat sink was created from a 5x7" sheet of 1/16" aluminum due to concerns about the stock setup's tendency to overheat. The propulsion unit was loosely bolted to the rear wheel of the Cannondale T-400 touring bike and was installed on the frame. The larger aluminum frame tubes caused the propulsion unit to press against the chain stays, necessitating additional grinding for clearance. The torque arm's hose clamp barely fit around the chain stay. The throttle was mounted upside-down on the top of the drop handlebars, and openings were covered with black duct tape. The throttle is operated by pulling it up with the index and middle fingers, which is comfortable. The battery mounting scheme did not fit within the frame triangle due to the thicker frame tubes, so the battery box was modified by removing the fastening tab and securing the front of the box to the top tube with a long hose clamp. The seat tube bracket functioned adequately. Throughout this process, the batteries were charged with the supplied charger, which was mistakenly sent in duplicate. These chargers are labeled as 2 amps and appear to be quite intelligent. When the battery reached 30V, the charger switched to float mode at 27.3V. The charger dimensions are 3x6x12 cm and it is lightweight. It is a switching supply that caused some interference with a nearby television. The first charge duration was 3 hours. A test ride around the neighborhood revealed that the acceleration was initially surprising, and the operation was quieter than expected, producing a whirring sound that diminishes at higher speeds. The weight distribution was satisfactory, without negatively impacting handling. The rider weighs 145 lbs, and while the bike's total weight with the kit has not been measured, it remains manageable when carrying it up a flight of stairs. Tire pressure for the 32mm Continental Top Touring tires was increased by 5 psi to 65 psi in the front and 75 psi in the rear.

The electric bicycle conversion kit described features a robust 600W motor, which is capable of providing sufficient power for urban commuting and recreational cycling. The motor's design allows for effective midrange torque, enabling the rider to maintain speeds up to 20 mph comfortably. The integration of the motor with the rear wheel through an adapter ensures seamless power delivery, although it requires careful consideration during installation to accommodate different frame geometries.

The modifications made to the Cannondale touring bike highlight the necessity of customizing electric conversion kits to fit specific bicycle models, particularly those with non-standard frame dimensions. The grinding of notches in the drive plate and propulsion unit demonstrates the practical adjustments often required to ensure compatibility and functionality. The addition of a heat sink is a critical enhancement, addressing potential overheating issues that could arise from prolonged use of the motor.

The throttle's unique mounting position and the use of duct tape for sealing openings illustrate the resourcefulness required in DIY electric bike modifications. The comfort and accessibility of the throttle position are essential for rider safety and ease of operation, particularly in urban environments where quick acceleration may be necessary.

The charging system, featuring intelligent chargers that switch to float mode, indicates a focus on battery longevity and efficient charging practices. The compact size and lightweight design of the charger facilitate easy transport and storage. However, the interference caused by the switching supply necessitates consideration of the charger’s placement relative to sensitive electronic devices.

Overall, this electric bicycle conversion exemplifies the blend of innovation and practicality, demonstrating how traditional bicycles can be transformed into efficient electric vehicles with thoughtful modifications and attention to detail. The rider's experience, characterized by satisfactory weight distribution and manageable handling, underscores the potential benefits of such conversions for everyday use.I went with electric because it`s quieter, not smelly and I can carry it up a flight of stairs. I chose the conversion kit made by Currie. Factory service is nonexistent, but EVdeals is a good, knowledgeable dealer. The motor delivers more than ½ horsepower (600W), which is plenty for a bike. Assistance is limited to about 20mph, but there is lots of midrange torque. The rear wheel is driven through an adapter which mates with the rear hub. I had to modify the system from the start because it was not designed to work with the fat frame tubes of my aluminum Cannondale touring bike. The kit is really geared toward steel frame mountain and hybrid bikes. I had to grind notches into the drive plate that holds the motor, gears and chain. I had to modify the battery mount. I added a voltmeter that indicates half the actual voltage (to gain a significant digit). I had to mount the throttle upside-down on the drop handle bars. Finally, I made a heat sink out of a 5x7" sheet of 1/16" aluminum. The stock setup is considered prone to overheating. I loosely bolted the propulsion unit to the rear wheel of my Cannondale T-400 touring bike and tried to install it on the frame.

All the frame tubes are larger, being aluminum. So the propulsion unit went against the chain stays. I ground a couple of notches into the propulsion unit to make clearance. It still touches the chain stays and I hope it won`t be a problem. The hose clamp for the torque arm barely made it around the fat chain stay. I mounted the throttle upside down on the top of my drop handlebars. I used some black duct tape to cover the openings. I work the throttle by pulling it up with my index and middle finger. It`s quite comfortable. The battery mounting scheme wouldn`t fit in the frame triangle, again because of the fat frame tubes. So I opened up the battery box and removed the tab for fastening with the key and strapped the front of the battery box to the top tube with a long hose clamp.

The seat tube bracket works OK. During all of this I charged the batteries with the supplied charger. They sent me two chargers, by mistake I assume. These chargers are labeled 2 amps and seem to be pretty smart. When the battery reached 30V it switched to float mode at 27. 3V. The charger is 3x6x12 cm and light. It`s a switching supply and caused some TV interference next to a TV with rabbit ears. The first charge took 3 hours. Yesterday evening I excitedly took the bike out for a spin around my neighborhood. The acceleration was a little startling at first and it was quieter than I thought it would be, a whirring that gets quieter up to speed. The weight distribution is good, it doesn`t seem to adversely affect the handling. I weigh 145lbs BTW. I haven`t weight the bike with the kit on but it`s tolerable carrying it up one flight of stairs. I increased the air in my (32mm) Conti. Top Touring tires 5 lb to 65psi front, 75ps 🔗 External reference