Bulked-up ebikes lugging large hub or mid motors and even larger batteries remain the industry standard, but a number of sleeker e-drive products have been moving ebikes' looks and weights closer to those of traditional bicycles. Scottish startup FreeFlow Technologies has pushed the latest slimmed-down e-drive toward the market, packaging its hardware neatly in the bicycle's bottom bracket.
Since its founding in 2012, FreeFlow has worked to develop a scalable electric drive designed to be integrated into ebikes of different styles during manufacturing. Its aim has been to develop an e-drive with exceptional power-to-weight ratio, and its current version offers up to 290 W of peak power at a weight between 5.5 and 7.7 lb (2.5 and 3.5 kg). The lithium-ion battery adds between 3.3 and 5.5 lb (1.5 and 2.5 kg), depending upon capacity.
Unlike the typical bulging mid-drive, the FreeFlow drive integrates more neatly with the frame and chainring. Spin the bike around, and while you do notice the drive behind the left pedal, it's not nearly as large and bulky as other mid-motor systems. In addition to the motor, the drive includes patented transmission hardware. FreeFlow says that it promotes clean, natural pedaling without the pedaling resistance felt with some e-drive systems.
As far as the battery, manufacturers can install it directly inside the down tube or attach it externally. A second range-extender can also be used with the FreeFlow system.
Specs like torque and range will vary by manufacturer and model, but the FreeFlow drive will offer multiple output modes and assisted speeds up to 15.5 mph (25 km/h). The battery will take between four and five hours to fully charge.
While certainly compact and low-profile, the FreeFlow drive isn't the lightest, sleekest ebike mid-drive to hit the market. The completely tube-integrated Vivax Assist, which evolved from the Gruber drive but was discontinued in 2020, weighed under 4.4 lb (2 kg) with battery and was so compact and unnoticeable, it found itself at the heart of "mechanical doping" controversies involving the possibility of pro cyclists using it to cheat. The similarly tube-integrated HPS Watt Assist Pro system features in one of the world's lightest electric road bikes, the 18.7-lb (8.5-kg) Domestique, but relies on a larger, heavier external battery than the Vivax Assist.
Other systems with which the FreeFlow drive will compete include the light but conspicuous 8.8-lb (4-kg) Bikee Lightest, the down tube-flaring 7.7-lb (3.5-kg) Maxon Bikedrive Air, and the modular 9.7-lb (4.4-kg) Ride 50, the latest evolution of the bottom bracket-integrated Fazua drive that has previously featured on bikes from Trek and Nox, among others. All weights include the respective battery packs.
In November 2021, FreeFlow announced its first OEM partner in British wooden gravel bike builder Twnpa Cycles, which has been testing a prototype wood bike with FreeFlow drive. FreeFlow says that it's also received interest from dozens of other bicycle manufacturers and sees its hardware being integrated into everything from mountain bikes to road commuters.
FreeFlow announced on Monday that it is moving into production after raising £1.65 million (approx. US$2.2 million) in its latest funding round. We'll be keeping an eye out for the first FreeFlow-driven production bikes.
Source: FreeFlow Technologies
