I've just finished setting up my GF's bike, an EZ-3 LWB recumbent, with a kit purchased from bmsbattery last month. This is a front wheel hub motor in 20" (406) size. Judy Liu of bmsbattery didn't seem to be familiar with the 406mm designation for 20" rims (as opposed to the 451mm which is also called 20" and I think there are a few others too) but the rim they sent is definitely a 406. I ordered the wheel built with the Bafang 350W high speed motor. The kit also included a KU93 controller and a thumb throttle. I also ordered their bottle battery, the 36V 8.8 Ah one. The kit arrived in about 2 weeks from the time I ordered it and it was well packed and complete. The wheel is true, with a rim that has machined braking surfaces. I mounted a Schwalbe Marathon tire with a Presta valve tube - had to use an adapter as the rim is drilled for a Schrader valve. I ordered a torque arm from ebikes.ca to use with this kit even though I don't think it is necessary at this power level - better safe than sorry and all that.
Installing the wheel on the fork was fairly straightforward - the kit came with a pair of torque washers (I think that's what they're called - the ones with the little tab that fits in the dropout and prevents rotation), two nuts for the axle and two flat washers to fit between the dropouts and the nuts, but no other washers/spacers. The axle is plenty long enough to accommodate the ebikes.ca torque arm and a couple of thick stainless washers that I made on my lathe. One washer .25" thick and one washer .125" thick let me get the wheel centered in the fork.
I decided to mount the battery holder under the frame's twin top tubes partially underneath the seat. A single hose clamp around the holder holds it in place. As this is a non standard arrangement I added a nylon strap around the battery and the frame as a backup. The controller is mounted on the seat back supports with a couple of aluminum straps and some tie wraps - nothing fancy but I think it'll hold.
I replaced the power connectors that came on the controller with Andersons so it would be possible to install a Watt's Up meter for initial tuning - I've put Anderson 30 amp connectors on the WU so I can use it for various measurements on my ebikes. I also had to splice the throttle and motor wires to make them long enough for this bike, adding about 18 inches to each.
The battery connector that came with the kit was supplied bare so I soldered 4 pieces of 16 gauge wire to it and put Andersons on the other end of two of them, the others I covered with shrink tube so they are available if I ever need them - maybe to add lights or something. The battery output connector is a 4 pin one, with two pins being negative and two positive. The controller needs two positive connections to enable throttle function so I added a short piece of wire with another Anderson connector to the main positive connection. Another Anderson on the controller lets me connect that.
So after all this I took the bike for a ride around the block with my Watt's Up meter in series with the battery connection. When I got home I looked at the WU readouts and found that the motor had drawn a peak of about 24 amps and the peak power was about 800 watts. This is too much for the 8.8Ah bottle battery so I opened up the controller and snipped one of the shunts. Another ride around the block and I read a peak current of about 12 amps and peak power of about 435 watts - that's more like it.
BTW I am running this setup sensorless - seems fine so far. The Hall wires are in the cable bundle from the motor but I don't see any reason to use them.
The next step is to let my GF take the bike for a longer ride and see how everything holds together. This motor setup is intended to be an assist like my EZ setups on my bikes so I think it will be adequate. If we want to go fast we take our motorcycles.
To sum up I'm pleased with the quality of the kit from bmsbattery and will remain pleased if it holds together.
Installing the wheel on the fork was fairly straightforward - the kit came with a pair of torque washers (I think that's what they're called - the ones with the little tab that fits in the dropout and prevents rotation), two nuts for the axle and two flat washers to fit between the dropouts and the nuts, but no other washers/spacers. The axle is plenty long enough to accommodate the ebikes.ca torque arm and a couple of thick stainless washers that I made on my lathe. One washer .25" thick and one washer .125" thick let me get the wheel centered in the fork.
I decided to mount the battery holder under the frame's twin top tubes partially underneath the seat. A single hose clamp around the holder holds it in place. As this is a non standard arrangement I added a nylon strap around the battery and the frame as a backup. The controller is mounted on the seat back supports with a couple of aluminum straps and some tie wraps - nothing fancy but I think it'll hold.
I replaced the power connectors that came on the controller with Andersons so it would be possible to install a Watt's Up meter for initial tuning - I've put Anderson 30 amp connectors on the WU so I can use it for various measurements on my ebikes. I also had to splice the throttle and motor wires to make them long enough for this bike, adding about 18 inches to each.
The battery connector that came with the kit was supplied bare so I soldered 4 pieces of 16 gauge wire to it and put Andersons on the other end of two of them, the others I covered with shrink tube so they are available if I ever need them - maybe to add lights or something. The battery output connector is a 4 pin one, with two pins being negative and two positive. The controller needs two positive connections to enable throttle function so I added a short piece of wire with another Anderson connector to the main positive connection. Another Anderson on the controller lets me connect that.
So after all this I took the bike for a ride around the block with my Watt's Up meter in series with the battery connection. When I got home I looked at the WU readouts and found that the motor had drawn a peak of about 24 amps and the peak power was about 800 watts. This is too much for the 8.8Ah bottle battery so I opened up the controller and snipped one of the shunts. Another ride around the block and I read a peak current of about 12 amps and peak power of about 435 watts - that's more like it.
BTW I am running this setup sensorless - seems fine so far. The Hall wires are in the cable bundle from the motor but I don't see any reason to use them.
The next step is to let my GF take the bike for a longer ride and see how everything holds together. This motor setup is intended to be an assist like my EZ setups on my bikes so I think it will be adequate. If we want to go fast we take our motorcycles.
To sum up I'm pleased with the quality of the kit from bmsbattery and will remain pleased if it holds together.
