Trying to increase my speed

Jshow73

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I have a e-bike that has 2 bafang 500 hub motors with 2 sealed controllers that are 750w 19 ah and it’s all 48v. I maxed out the settings on the display but 22 is the top speed. I’m sure there is a way to disable the speed limiter but all my controller wires are accounted for and theres no extra wires so I’m asking if there’s something with the motors that could limit the speed
 
Yes. They were designed to go 22mph at 48V. Next time, buy motors with a higher designed-in speed, or get a higher-voltage battery.
 
You spent a lot of money on a product which will not do what you want it to do. Many people do this, for many reasons but often for the very one you fell for.

Understanding the most basic specs of an ebike is something you failed to do. This has made you unhappy, as it has made many people unhappy.
By putting forth a clear example of, and explanation as to how, you and many others have found themselves in an unhappy situation, hopefully many people will take a few moments of their time and do just a bit of fact-finding to prevent this negative outcome, and get instead a product which will do what they want it to do. Thereby Preventing great sorrow, lament, and rending of garments.

I look upon it as spreading happiness and great joy amongst the multitudes. You just have a negative outlook on life.

Oh, and 19 Ah is a battery spec, not a controller. 19 max amps on each controller with a 54.6V battery is pushing 1,000 watts per motor. If that is, in fact, the controller spec especially considering you have two motors, that just indicates you should not be amp-limited, plus 22mph is not a legally required speed limit anywhere, it is just your motor's Kv rating is too low.

Unless of course the bike is carrying a Very Heavy load, then it could be amp-limited, but since you did not define in weight terms just exactly how wide your ass is, just in attitude, I have to make certain standardized assumptions.
 
22 mph on a 48v system - particularly a fat geared hub - is about right. You could take it up to 23 or 24 given the right circumstances, but your bike is performing about where it should be for a 48v system that is also probably pretty heavy given its got the weight of two motors, and probably a pretty big battery to boot.

A 2wd bike is not going to go twice as fast. You'll get a little more speed out of it, but only a little. My 35a, 52v fat 2wd is good for about 31 mph on a single motor. Two motors: 34 mph. And that will drop right off as the battery runs down. 2wd is about the benefits of distributed traction, not higher speed. It also makes the motors run a LOT cooler than just one would, but thats not something anyone asks for when they are thinking of a 2wd bike. Its just a noteworthy side effect.

For what its worth, its the voltage that decides your top speed, not the controller amps. The amps determine the strength of your acceleration. To use more broadly understood terms, here's a good (if technically inaccurate) way to think of volts and amps: Volts are horsepower. Horsepower increases top speed on a car. Amps are torque. Torque on a car determines how fast it accelerates. As the old saying goes: Horsepower sells cars, torque wins races.

If you have 19a controllers, and those controllers measure that '19' as a peak value, then you probably have an 8 or 9 amp continuous output rating on those controllers. Which ain't much. You've got a bike that is made to give you mild awd benefits and its never going to be a speed demon unless you start replacing parts like the battery and the controllers... which is going to get really pricey considering a battery that can handle that - two 35a peak controllers so a BMS capable of about 80a continuous is in order - has to be custom made. The controllers alone are about a hundred bucks each.

Probably better to just be happy with what you have, or sell it and build something truly fast.

 
22 mph on a 48v system - particularly a fat geared hub - is about right. You could take it up to 23 or 24 given the right circumstances, but your bike is performing about where it should be for a 48v system that is also probably pretty heavy given its got the weight of two motors, and probably a pretty big battery to boot.

A 2wd bike is not going to go twice as fast. You'll get a little more speed out of it, but only a little. My 35a, 52v fat 2wd is good for about 31 mph on a single motor. Two motors: 34 mph. And that will drop right off as the battery runs down. 2wd is about the benefits of distributed traction, not higher speed. It also makes the motors run a LOT cooler than just one would, but thats not something anyone asks for when they are thinking of a 2wd bike. Its just a noteworthy side effect.

For what its worth, its the voltage that decides your top speed, not the controller amps. The amps determine the strength of your acceleration. To use more broadly understood terms, here's a good (if technically inaccurate) way to think of volts and amps: Volts are horsepower. Horsepower increases top speed on a car. Amps are torque. Torque on a car determines how fast it accelerates. As the old saying goes: Horsepower sells cars, torque wins races.

If you have 19a controllers, and those controllers measure that '19' as a peak value, then you probably have an 8 or 9 amp continuous output rating on those controllers. Which ain't much. You've got a bike that is made to give you mild awd benefits and its never going to be a speed demon unless you start replacing parts like the battery and the controllers... which is going to get really pricey considering a battery that can handle that - two 35a peak controllers so a BMS capable of about 80a continuous is in order - has to be custom made. The controllers alone are about a hundred bucks each.

Probably better to just be happy with what you have, or sell it and build something truly fast.

I really appreciate your thoughtful response and will take all advice given. Thanks
 
My son in law went 68mph on a 1500watt rear hub motor. At first test ride, a bit too much throttle off the line, and it ripped the tire right off the rim. His secret was to put two batteries in series- a 48 volt and a 36 volt giving him 84 volts. I didn't ask for the rest of the details, not sure what type of controller was used, etc. I'm sure there's plenty of youtube videos on the matter, that's where he got his idea from.
 
My son in law went 68mph on a 1500watt rear hub motor. At first test ride, a bit too much throttle off the line, and it ripped the tire right off the rim. His secret was to put two batteries in series- a 48 volt and a 36 volt giving him 84 volts. I didn't ask for the rest of the details, not sure what type of controller was used, etc. I'm sure there's plenty of youtube videos on the matter, that's where he got his idea from.

And to think, I get nervous when my bike cracks 20 MPH. :)
 
with your motor being wound to give you about 22mph top speed with 48v battery you MIGHT even be able to get as fast as 24mph when your battery is fully charged and at 54 volts but only for the first few miles before the voltage in the battery drops some.

tho with all that wattage and two motors, you might be able to go up hills faster than you might of other wise been able to with less wattage and only 1 motor.
 
I read your title and my immediate thought was - pedal faster. Then I remembered this isn't a cycling forum.
 
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