MikeSSS
1 kW
Did a test ride, 6.3 miles, same route and speed, same battery, one bike with geared front hub, the other with direct drive front hub, same rider.
The geared hub was a front Bafang G311, a small 11:1 reduction gear hub, on a 24" wheel Townie, with a 32 x 14 top gear and a 36v, 10ah battery charged to 42.0v. Rider weighed 210 lb total and pedaled on the flats and climbs. Average speed was 10.6 mph.
The direct drive hub was a front Aotema, on a 26" Jamis Hudson, much like a Townie, with 42 x 14 top gear but downshifted a couple cogs to match the gearing of the Townie. Same battery and rider were used, average speed was also 10.6 mph.
Result: voltage final was 40.1v for the gear hub Townie and 39.8v for the direct drive Hudson. That's not a big difference, charge time was less for the Townie run than for the Hudson, as would be expected. 0.92 hrs vs 1.03 hrs, both at 2 amps and titrated to a full 42.0v charge. While not a big difference it would give the Townie about an extra mile of range, using battery voltage from 41v to 35v. I expected a bigger difference, the actual advantage was probably mostly due to tires rather than hub motor type.
Tires were Kenda K-838 24" x 1.95 on the Townie and Performance Gotham 26" x 1.75 on the front of the Hudson and no name tire on the rear.
Coast down testing of my bikes, overtaking my wife's bike, pedal only, no hub motors, revealed that Kenda 838 26" x 1.95 on my FS bike versus Gotham 26" x 1.75 on another of my bikes, showed the 838's have significantly less rolling resistance than the Gothams.
Well, I was wondering about geared hub vs direct drive and got a surprising answer.
The geared hub was a front Bafang G311, a small 11:1 reduction gear hub, on a 24" wheel Townie, with a 32 x 14 top gear and a 36v, 10ah battery charged to 42.0v. Rider weighed 210 lb total and pedaled on the flats and climbs. Average speed was 10.6 mph.
The direct drive hub was a front Aotema, on a 26" Jamis Hudson, much like a Townie, with 42 x 14 top gear but downshifted a couple cogs to match the gearing of the Townie. Same battery and rider were used, average speed was also 10.6 mph.
Result: voltage final was 40.1v for the gear hub Townie and 39.8v for the direct drive Hudson. That's not a big difference, charge time was less for the Townie run than for the Hudson, as would be expected. 0.92 hrs vs 1.03 hrs, both at 2 amps and titrated to a full 42.0v charge. While not a big difference it would give the Townie about an extra mile of range, using battery voltage from 41v to 35v. I expected a bigger difference, the actual advantage was probably mostly due to tires rather than hub motor type.
Tires were Kenda K-838 24" x 1.95 on the Townie and Performance Gotham 26" x 1.75 on the front of the Hudson and no name tire on the rear.
Coast down testing of my bikes, overtaking my wife's bike, pedal only, no hub motors, revealed that Kenda 838 26" x 1.95 on my FS bike versus Gotham 26" x 1.75 on another of my bikes, showed the 838's have significantly less rolling resistance than the Gothams.
Well, I was wondering about geared hub vs direct drive and got a surprising answer.