Cadence vs Assist

[smokey_jo]

So am I correct in understanding that the less pressure I put on the pedals the less assistance the motor will provide?
And if so does pedalling high cadence and smooth rather than slow cadence and pushing hard on the pedals help to extend the range?

 

[Eckythump]

It depends on the motor you have. Bosch & Brose like high cadence, Yamaha lower & Shimano somewhere in between.
My experience with Shimano is is the more you spin the more efficient it is.

 

[smokey_jo]

Mines a Shimano E8000 - my cadence tends to be low to mid eighties - might try and increase this then to eke out a bit more range

 

[eFat]

So am I correct in understanding that the less pressure I put on the pedals the less assistance the motor will provide?

Yes.

But in the end I'm not so sure it makes that much difference on the range. Less pressure & less assistance => pedal longer => identical consumption?

I had done a little experiment, 1 km with 10% incline at different paces (several times).

With a Bosch motor in Eco mode.

1. slow, effortless (I produced an average of 170W and 70rpm during 399s)
2. high cadence (200W, 90rpm, 354s)
3. pushing hard on the pedals (235W, 75rpm, 300s)

But in the end the energy consumption was identical around 17Wh/km.

The only thing that had a direct impact on the consumption was the assistance mode.

 

[smokey_jo]

So for 2 people and bike of equal weight on an identical route on identical bikes in the same power setting there will be little difference in how much battery is consumed regardless of pedalling effort or cadence?

 

[Kernow]

Mines a Shimano E8000 - my cadence tends to be low to mid eighties - might try and increase this then to eke out a bit more range

I think a cadence in the eighties is spot on , and that’s where the shimano is best , I don’t think you’ll get any more battery life from spinning faster than 90 , more likely to just wear yourself out faster then have to rely more on the battery . I think Efat has it correct there , wieght is the biggest factor , my battery lasts less time than a rider 20 kg lighter than me , we’ve proved that on many rides with identical bikes .

 

[eFat]

So for 2 people and bike of equal weight on an identical route on identical bikes in the same power setting there will be little difference in how much battery is consumed regardless of pedalling effort or cadence?

I would think so... with a restriction: Each setting provides a maximum output and once it's reached you can push harder but the motor won't help you more. Maybe my experiment would make more sense with maximum assist?

 

[Blackbird]

eBike range calculator for Bosch drive systems – Bosch eBike
The bosch range calculator shows that the higher the cadence the more range you will get.

 

[Kernow]

eBike range calculator for Bosch drive systems – Bosch eBike
The bosch range calculator shows that the higher the cadence the more range you will get.

That calculator is even more optimistic than shimano , according to that 111 mile range at 10 mph is possible for a heavy person , there would be a lot of stranded riders if we planned our rides according to what the computer says , very corbynistic

 

[Blackbird]

Oh sure, although it is fun to play around with the settings to see the effect of higher speed on battery usage.

 

[Eckythump]

I think with torque sensing motors you get better efficiencies at higher cadence as you cannot spin fast and apply high torque at the same time.
Grinding hard at lower cadence seems to really eat up the watts.