They're what came with my motor, a bafeng 36v250w SWXK2 (or the older variant) fitted to a Brompton front wheel by the guy I brought it from. He did it about 10 years ago then sold it to me a few years ago.
The conversion kit came with torque plates that go inside or outside the fork - I'm not sure which is best. Perhaps you can tell me the best way to set it up, see pics below.
I love taking my electric converted brompton off-road. I come from a MTB background but age, bust knees and small London home mean I don't ride much any more. Getting my Brompton was marvellous - could take it on the train, bus, taxi etc. It's been to Scotland, Wales, Lake District etc. I've taken it around BMX courses, motocross courses (that was a foot deep in mud) etc. Even better when I converted it to an ebike a few years ago.
I was rock-crawling on it in Scotland, tried to power over a boulder, and the front wheel motor broke the torque plate and went walkies. Might have lost the washer then, or a few days later when I put the old non-ebike fork and normal wheel back on.
Pics below of the torque plates - bust and non-bust - and how I had them on my bike. Did I have them on the wrong way round? Any idea where I can get new ones?
Probably not replaceable, so will put torque arms on. I unfortunately bought two of the shitty Chinese ones & found they don't fit.
Problem 1: The 10mm flats on the axle only extend out about 4mm from the body of the motor. With a standard Chinese torque arm (30mm long comma shaped body), the connecting bolt rubs on the body of the motor. Needs around 45mm centre to centre between the axle and the connecting bolt for it to clear. On this side, I can put the torque arm directly on without a torque washer. 12mm clearance needed.
Problem 2: On one side, the axle flats are within a rim on the motor & the only part that sticks out is the tab of the torque washer. Torque arm needs 14mm hole to fit over axle plus tab of torque washer.
The Grin V3 torque arm is obviously the best one, but the cheapest I can find for it in the UK is
on eBay at £38 inc postage - £76 for a pair. Fook me! (Edit: Alibaba has them for £10 plus £25 delivery each, no thanks)
An Ukraine seller is
selling a pair of 14mm Grin V3 style arms at £25 inc delivery, but they look like copies, and means waiting for delivery. (Also means the arm on one side will have a 14mm hole on a 12mm axle.) What do you think of them?
(Same guy
also has this one, strange design)
Cheers T
(Imgur links if you cant see the pics below:
pic 1,
pic2.)
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