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Can I get more range out of my e-bike if I put a speed limit on it?

I got my bike a few days ago and I really am enjoying it. As of now I am getting about 35 km per charge. So I was wondering if I am able to get more range by putting speed limit on the bike.

I tried putting the speed limit and I hope I will not cause any damages.

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    How are you speed limiting your eBike? It depends whether the motor ends up working less or not. – IKY.LI Jan 23 '18 at 10:42
  • I have a monitor on my bike thst gives me the option of speeds. Right now there is no limit on the bike . It can go as fast as 50KM per hour and it gives me a range of about 35KM per charge. So if I give it a limit of 35KM per hour will it increase my range? – eitanben Jan 23 '18 at 10:53
  • Curiously, what are the legal wattage and/or speed limits in your area of the world? Different locations mandate one or the other, rarely both. – Criggie Jan 23 '18 at 11:07
  • 48v no speed limit depends on age. – eitanben Jan 23 '18 at 11:23
  • @Criggie the whole EU limits both (250W and 22km/h IIRC) – Chris H Jan 23 '18 at 12:36
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Depends totally on your bike's Battery Management System and what options it offers.

Generally speaking, a battery has a certain amount of stored energy, which is its capacity in watt-hours, which may be expressed in amp-hours (at a known voltage).

Functionally, a battery could put out energy at half the maximum rate, for twice as long. If your bike's BMS lets you choose a lower level of assist, then it will get you further on a charge.

Excessive speed also costs you in power - at 15 km/h roughly 10% of your power goes into aerodynamic drag, with the bulk as rolling resistance and friction. At 40 km/h your rolling resistance power loss remains about the same in terms of watts, but the aero losses are now 75-80% of your power usage. So you're using 5× as much power to cover the same distance, at 3× the speed. (figures are for a road bike; it's worse for a less aero bike)

If your bike has a throttle and not pedal assistance, then get it up to a safe riding speed and stop using the throttle. Pedal to keep it at that speed, only use the motor to accelerate or to climb hills.

Remember in the end it's an assistance system, not a replacement for pedalling. If you're treating it like an electric motorbike, then start pedalling and that will extend your range incredibly.

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    If you're sitting statically on a moving bike, its dangerous because motorists won't perceive your true speed. Pedalling makes you look like a moving bike, and they're slightly more likely to notice you. – Criggie Jan 23 '18 at 11:05
  • But if i put A speed limit to try it out could it damage the bike or battery? – eitanben Jan 23 '18 at 11:12
  • @eitanben You could easily damage something if you make a mistake, but a correctly installed limit switch can only help. Also running at maximum output can lead to inefficiency in the electronics (though a badly designed system can be inefficient at low powers) – Chris H Jan 23 '18 at 12:40
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    If the bike has a built in system that can limit it's speed, then using it will not damage it. – Argenti Apparatus Jan 23 '18 at 13:01
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    @eitanben If you limit the speed using a brake, you're wasting energy. If you limit the max speed using the software in the controller of your bike (its BMS) then you're doing it right. Read the manual for your bike's controller. – Criggie Jan 23 '18 at 21:25

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