Bbs01 and gearing ratios.

[jimriley]

Hi. I've been playing with the gearing on my hybrid. Originally 700c with 34-13 x 7 and the bafang 46t front cog. Restricted to 15mph.
The first change was to fit a 34-11 x 7. That increased the top speed derestricted, in the grounds of the mansion obvs. It had to be tried though.
Don't intend to use it like that on the roads and tracks around, it was struggling on steep bits on tracks and paths.

Now fitted a 44t front cog, it's great. Top speed pushing pedals was about 23mph, bottom gear vastly improved, motor spinning faster, as it should.
I've tweaked to 100 % keep current and speed on the 9 levels, it was a joy to ride on a mix of bumpy track and canal towpath.
The other benefit, although it might be slow, it will be OK to pedal if the battery dies.

 

[egroover]

I run a 10 speed 11-36 x 46t chainwheel on my 700c wheeled hybrid with a bbs01
Just about to build another bbs01 conversion with my 26" wheeled MTB , so will be using the supplied 44t chainwheel with a sunrace 9 speed 11-40, hopefully give me enough low down gearing for off road riding

 

[Deleted member 33385]

Hi. I've been playing with the gearing on my hybrid. Originally 700c with 34-13 x 7 and the bafang 46t front cog. Restricted to 15mph.
The first change was to fit a 34-11 x 7. That increased the top speed derestricted, in the grounds of the mansion obvs. It had to be tried though.
Don't intend to use it like that on the roads and tracks around, it was struggling on steep bits on tracks and paths.

Now fitted a 44t front cog, it's great. Top speed pushing pedals was about 23mph, bottom gear vastly improved, motor spinning faster, as it should.
I've tweaked to 100 % keep current and speed on the 9 levels, it was a joy to ride on a mix of bumpy track and canal towpath.
The other benefit, although it might be slow, it will be OK to pedal if the battery dies.

Yes, I've settled on the 44T too - tried 48 and 52 but I can manage hills on the 44T unpowered, albeit very slowly, plus it's fast enough for me to accept. The cadence under power with the Bafangs would definitely be improved with a torque sensor of some sort, as I always end up either chasing the motor or by bike not being powered enough - overall a torque sensor would make the system more efficient and get more miles out of the battery. That being said, I've still got 40% battery after a total of 36.8 miles while making almost zero effort pedalling, with 100% motor assistance at all times over hilly terrain.