Best way to climb a hill for battery/motor health

anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
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So if you spin slower than the motor's optimum speed, then you waste battery power through winding heat losses.
But what happens if you spin your legs FASTER than the motors optimum speed? (so you're way above the power band and the motor is still spinning, but not giving much if any assistance)
The GSM creates enough back EMF to cut out at about 95 rpm. That is why I have decided to up the voltage a little. Seems to work on short test runs so far but need to try the big hill before making a serious opinion.
 

Gubbins

Esteemed Pedelecer
I am genuinely interested in this advantage. And this thread is about what's best for the battery etc, so ....
Is the advantage that you've found if you spin fairly fast, you use less battery power and so extend the range?

(and FWIW, my wife seems to prefer the Yamaha motor to Bosch CX in terms of smooth power delivery!)
To be fair when this section was set up it was for totally legal emtb bikes and my giant doesn't fall into that catergorie. So pm'd you
 
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soundwave

Esteemed Pedelecer
May 23, 2015
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So if you spin slower than the motor's optimum speed, then you waste battery power through winding heat losses.
But what happens if you spin your legs FASTER than the motors optimum speed? (so you're way above the power band and the motor is still spinning, but not giving much if any assistance)
you try peddling at 120 rpm for any length of time not going to happen but climbing steep hills or maxing out the rpm for max speed does the same thing nuke the batt so as i cant keep at 120rpm my range on flat is about 25 miles.

tho climbing hills you will use more torque and more power but at a slower speed but use even more power and get 10 miles range non stop climb.
 

Gubbins

Esteemed Pedelecer
So if you spin slower than the motor's optimum speed, then you waste battery power through winding heat losses.
But what happens if you spin your legs FASTER than the motors optimum speed? (so you're way above the power band and the motor is still spinning, but not giving much if any assistance)
If you can spin in excess of 100 without suffering then you are more likely to be able to stay above the cutoff thereby increasing range.
 

E-Wheels

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Aug 16, 2016
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If you can spin in excess of 100 without suffering then you are more likely to be able to stay above the cutoff thereby increasing range.
If you could spin >100rpm for any length of time then you probably wouldn’t need an ebike??
 

Gubbins

Esteemed Pedelecer
If you could spin >100rpm for any length of time then you probably wouldn’t need an ebike??
Ah well, Turning your legs fast is one thing, getting an old man up 1000ft+ is entirely another. I have been told that if you turn you legs fast enough it will go uphil with little effort.. What utter tosh!!
 

anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
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If you could spin >100rpm for any length of time then you probably wouldn’t need an ebike??
I agree with Gubbins 100 rpm isn't hard to maintain for me it is a question of the type of muscle tissue you have in your legs not how much muscle tissue.

Having a motor allows me to spin for 4 hours on end whatever the slope. I have done a complicated ride on my motorless trike with slopes that had me down to 30 rpm and I managed about 50 km, with a motor I would do 100 km on the same terrain.