E-bike w/ 48v 10 Ah battery used at low speeds mostly

Santa

Member
Region
USA
If an e-bike has a rear hub 48v & 500w and is using a 10 Ah battery and a person pedals and rides at the lowest speed setting ( w/motor assist), is it harder on the motor and battery than a higher speed ? Heat ? I’m an old mechanical guy. Build lots of stuff out of metal. Electronic not somuch.
 
Answering that is not easy.

With the hub-drive motor, it is the motor that sets the actual speed of the e-bike, and that speed depends on the PAS assistance level and the throttle position. The rider only adds the additional power by pedalling but he/she has to pedal as fast as to match the motor speed, and that's where the derailleur comes handy (to match the pedalling cadence to the current motor speed).

Now, hub-drive motors like to be spinning fast, so throttling the motor down in Assistance Level 1 makes the motor work in its inefficient region. Thus riding a hub-drive motor e-bike very slowly is not recommended.

The remarks above are for hub-drive motor e-bikes. Mid-drives work on a different principle and can be ridden very slowly if needed.

In any case, slow rides are beneficial to the battery, as there is a little air drag, and far less of the battery charge is used than it is with fast rides.
 
Higher currents wear out the battery more. If grades are moderate, then low speed is good. If the motor is really straining to carry you, then faster speed on steep grades is better.
On the rolling hills in my country, I usually let the momentum build downhill up to 30 mph, then apply the throttle midway up the next hill. Over 30, I might hit a deer. They are as stupid about vehicles as rabbits.
 
The question is interesting, but why worry? I assume the motor designers built them to run at biking speeds, between 10 and 18 mph

Heat is what wears out electrical components, so keep the current low, and the parts are happier. While you have the question of efficiency, you have to trust that the motor designer covered that. The motor nerds are usually talking about losses and magnetic soaking and stuff that happens at high speed.

I ow, a half dozen hubmotor bikes. Run all the time at 12 mph, Nothing gets hot. Nothing fails, unless you get them water inside the works. A printed circit land will boil away in seconds if it's wet.





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Higher currents wear out the battery more. If grades are moderate, then low speed is good. If the motor is really straining to carry you, then faster speed on steep grades is better.
On the rolling hills in my country, I usually let the momentum build downhill up to 30 mph, then apply the throttle midway up the next hill. Over 30, I might hit a deer. They are as stupid about vehicles as rabbits.
rabbits? there are more deer than rabbits laying along the roads here(deer used to be scarce around here,maybe the rabbits have had more time to acclimate) i really appreciate your hub motor experience and have learned a lot from you.one thing members have to appreciate us folks on the upper end of the age scale have to watch the pennies in the cookie jar,so we look for"bang for buck",the main reason i like a throttle is to get going on a steep hill,the tactic of diving down and abrupt 180 doesnt always work so good. my current desire is a lighter weight bike( stealthy as well) like a propella or a reverse trike( balance issues) i actually worked 3 days this past week(107) yesterday and if it had been more than 8 hrs i wouldnt have made it actually lost about 4 lbs yesterday, so no"breaking away" for this old galute,and its really a shame the trail bikes and heavys have destroyed the dirt road i used to ride on so maybe its time for something else.
 
To throw a bit of opinion on Santa's question, you will need to huff the pedals at a real low PAS setting. I'm outta shape and my Lectric ebikes are heavy, inefficient monsters. I can't keep up a doable cadence in PAS 1 or 2 unless I like going REALLY slow, so my ebikes live in PAS 3 most of the time. I still have my analog bike for a workout! I'm happy at 13mph on the ebikes, and so are my flabby legs, especially with my wife on the back. PAS 1 and 2 require more pedal effort that my outta shape butt can supply so PAS 3 is my sweet spot. My motor has never felt hot at slower speeds or when we wind it out going home in PAS 5 with me cranking on the pedals. I can still sprint when needed.

I do drop in lower PAS levels to get a bit of a work-out once in awhile. I have 250 miles on the XP and around 400 on the Xpedition and neither one feels any different from when new. The motors have a pretty good punch of power and I do touch them afters long slogs and have never felt them get hot.
 
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