Electrify-it-Yourself: Introducing the Lightest Mid-Drive Kit We’ve Seen Yet

Paul Daniel, formerly an engineer at Brammo Electric Motorcycles, is on a quest to develop the ultimate mid-drive for electric bicycles. Several iterations produced during the past ten years include the bike that won the inaugural Arizona Death Race in 2011, the second e-bike ever exhibited at the North American Handmade Bicycle Show in 2014, and a bike he raced successfully at the Sea Otter e-MTB race in 2017.

Recently, BICYCLIST had the opportunity to examine the culmination of Paul’s efforts, the Revel Propulsion. The kit arrived packaged extremely well and was a masterpiece of design and engineering. The motor, controller, display which changes from Class I (20 mph) to Class III (28 mph) and back by switching from one mode to the other. Parts used for installation weigh slightly less than eight pounds on the recently calibrated BICYCLIST Freedom Units scale, while the battery weighs about four pounds.  This 12 pound total makes the kit the lightest do-it yourself (DIY) mid-drive that we’re aware of (it should be noted that the kit replaces the bottom bracket and crankset on the bike; usually this weight is in excess of two pounds, so the kit addition is less than 10 pounds).

The kit produces 60NM of torque making it slightly less powerful than most OEM combinations. Paul has designed this product for riders who want some boost, but still desire a pedaling experience. Additionally, the system has a very expensive torque sensing bottom bracket, one of the few DIY products with this feature. This will increase the seamlessness of the transition as the motor’s power is incorporated.