sdobbie
100 W
I have a Dawes Suburbia Boost electric bike. The motor on it is a geared hub motor with nylon gears in it. Could this motor be run at 350w?
Running 250w motor at 350w
- Thread starter sdobbie
- Start date
emmetbrown
10 W
Can't say it for sure.
I have a similar nylon-geared rear hub that will take 500 watts without a problem.
At 1 Kw it makes an unhealthy noise.
christian
I have a similar nylon-geared rear hub that will take 500 watts without a problem.
At 1 Kw it makes an unhealthy noise.
christian
The power rating 250w doesn't mean anything, and neither does 350w
Are you looking for more speed or climbing power? Your motor can handle both. If you need more torque for climbing, you can solder the shunt in your controller to increase it by about 25%, which doesn't cost anything.
Are you looking for more speed or climbing power? Your motor can handle both. If you need more torque for climbing, you can solder the shunt in your controller to increase it by about 25%, which doesn't cost anything.
sdobbie
100 W
d8veh said:
I was wanting more speed and power because the bike is like a tired snail as standard. I have a small 6 mosfet controller which I replaced all the mosfets with IRFB4110 and thickened the shunt to give 800w for a previous bike. The current controller in the bike is 250w and limits the motor to 15 mph. I got the new bike because it is lighter and I wanted a battery that can be locked into the bike to protect from theft rather than looking like a terrorist with a load of massive lipo's in my backpack.
The reason I got a new bike was because my old frame was unsuitable for the weight of 1.1 Kwh of lipo's, it was very hard to pedal if the motor failed Plus I was running 2000 watts through an 800w motor which resulted in damage to the wheel. It was great to ride, the acceleration to its maximum speed of 24mph was amazing. It was certainly a head turner.
wesnewell
100 GW
The watt rating on the motor and controller for that matter are continuous use ratings, not max watt ratings. A 250w rated controller may have a max watt output of 1000W or more depending on the voltage to it. A motor can take many times their rating for shorter periods of time. The gears is another story though. It would all depend on the durability of the gears, and the clutch. One reason I don't like geared motors. Just more stuff to break compared to a DD hub.
danielrlee
10 kW
I run a nylon geared hub motor originally rated for 250W at 1150W (50V 23A). As long as I don't let the motor get bogged down on the hills while I'm WOT, it seems to cope well. Mind you, I live in the UK. If we regularly experienced hotter weather, I suspect reliability would suffer.
sdobbie
100 W
danielrlee said:
I live in Fife in Scotland.
So does the manufacturer conservatively rate the motor at 250w to prevent it from being damaged by those who don't know any better giving it full power up steep hills without pedalling? I might try it at 500w, not give it full power on hills, check the temperature and inspect the gears regularly and see if it copes. I have an identical motor that takes 24v which can be used as spares if something does break.
They write 250w on the motor because that's what it has to have to comply with EN15194 to make it legal in Europe and Australia. It's actual rating could be anything. You can share people's experience from this forum of what these motors are capable of. From my experience 20 amps at 36v is still safe. 18 amps at 44v and 16 amps at 48v are also safe, but the higher the voltage, the more you have to be careful not to labour the motor up hills to avoid over-heating. You can go higher than those rattings, but you have to have a good understanding of how voltage and current effect efficiency and temperature.
sdobbie
100 W
d8veh said:
Thanks, that's cleared it up for me. I will replace the existing controller in the bike as it is limiting to 15mph and I have no idea how to disable the limit. I will try 500w and see how it goes.
