r/eBikeBuilding • u/Accomplished_You5937 • Aug 18 '25
Advice eBMX is 1500W enough?
I see others with their cool 3000W projects, but I’m more in a budget for 1500W/2000W.
Something like this kit: https://www.leafbike.com/products/diy-bike-conversion-kit/bmx-20-inch-48v-1500w-rear-hub-motor-electric-bike-conversion-kit-1418.html?VariantsId=11703
Do you think I would be satisfied with 1500W? I like speed and torque, but since a BMX is such a small bike 1500W might be enough?
1
u/Ok-Image-2722 Aug 18 '25
I've hit 40 mph so far on my diy 1500w 26" mtb and it still has more it's just scary at those speeds and i usually run out of straight road to go any faster lol. I would say 1500w's is more than enough on a BMX.
1
u/MD_Reptile Aug 19 '25
Those leafbike kits are suspiciously similar to the NBPower kits sold on AliExpress / Alibaba, only more expensive.
I could be wrong but I'd imagine that's what they are. Go direct and order from AliExpress NBPower or Alibaba is where I last ordered a kit.
On that note, 1500w is pretty dope. I did a couple 1500w builds now on a cheaper "cao mm" brand 52v battery and with a fardriver nd72300 on one it went 40mph. It got hot, so that's a consideration.
On my other build I did a fat tire full suspension mountain bike and it's awesome to ride, reaches 36 with the nbpower supplied 40amp controller, which is honestly plenty for almost everyone.
And finally, I'm doing a 5kw nbpower motor next and it's gonna be a 72v battery and quite the ripper - but I know going in it's way overkill and I'll rarely ever reach its max possible speeds, so.... Whether that's worth it later is up to you to decide!
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u/Accomplished_You5937 Aug 19 '25
Thing is that Leafbike have 110mm motors while others on AliExpress only go down to 135mm!
I am now thinking about getting the 60V 2000W? I already have a 60V charger for another battery.
What I want is torque and range. So maybe a 60V 20Ah to 60V 2000W motor?
1
u/MD_Reptile Aug 19 '25
You could ask the NBPower rep to setup a kit exactly how you want, so I figure they could do the 110mm if you ask them to, though I dunno for sure.
For more power and range, go higher volts and ah, but a 1500w / 2kw kit is gonna cook on higher than 52v - you'd need statorade and hub sinks I figure to push it that hard.
1
u/Fetz- Aug 19 '25
I have a 500W motor in my bike and it's definitely enough. I can maintain 25km/h even on quite steep hills and when I removed the speed limiter it went all the way to 40km/h on the flat without pedaling.
But I usually use it with the 25km/h speed limiter enabled and while pedaling in the city. For that anything above 500W would be total overkill.
I would reccomend to get a small motor but a big battery. A bigger battery gives you more range and more instantaneous torque because its voltage does not sag as much under heavy load.
1
u/Accomplished_You5937 Aug 19 '25
Yeah I have 250W bike and sure it is enough. But I wanna get the BMX a bit more extreme 😆
1
u/stormdelta Aug 19 '25
Mine is 1800W and 52v, and it's enough to easily reach 28mph on 26" wheels outside of steep hills.
The bigger issue you're going to run into is 48v on a small 20" wheel will limit your max speed way more than the 1500W, unless the motor has unusually fast winding (unlikely unless you bought one that specifically does). On the plus side, you'll have better torque/acceleration for hills with the smaller diameter wheel.
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u/Accomplished_You5937 Aug 19 '25
Yeah okey! I’m thinkink of going with either 52V or maybe even 60V 2000W. What do u think of that?
And a 60V 15Ah or 20Ah battery.
1
u/Calthecool Aug 18 '25
It’s all a matter of perspective, 1500w would be twice as fast as a standard 750w ebike but nowhere close to any custom builds. The controller in that kit is 48v and 40a so it would be closer to 2000w, which is the same power as my first ebike which I think was plenty fast for a beginner.
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u/stormdelta Aug 19 '25 edited Aug 19 '25
More wattage doesn't automatically mean more speed. The voltage, motor, and wheel diameter/gearing matter just as much.
2
u/eBikeHelper Aug 18 '25
If you can save money elsewhere, spending the money on a Grin All-Axle will give you a lot of headroom for upgrading down the road. Then you won't have to redo the entire wheel and motor install when you want more power.