I have a Generic 1000 watt front hub motor and the front wheel keeps coming loose. What should I do? I think I have heard of something called a torque arm. Will this help?

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    I'd recommend getting a real moped. Bicycles aren't designed for that kind of forces at front fork. – ojs Oct 19 '15 at 18:04
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    1000W is a lot of power, and to be much use on a bike it will also give a lot of torque. I bet the acceleration with that motor is impressive. That torque all acts on your forks. An axle with proper nuts on both ends is an absolute minimum. To give you an idea of how powerful this is, for use on public roads in Europe the legal limit is 250W (200W in some cases). Your frame may suffer under that power as well. – Chris H Oct 19 '15 at 18:11
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    Through bolt & torque arms are a must. Especially if your fork is aluminum & not steel. Anything else is just dangerous. I highly recommend reading up on the subject over at endless-sphere.com/forums For the record, most generic motors claiming 1000 watts don't really come close, even & "peak", it is probably more like a 350 or 500 watt in reality. I'd rather do something like this right & be as safe as possible, than do it cheap & put myself & others at risk. – renesis Oct 19 '15 at 18:25
  • See this question for useful suggestions. Note the "anything more than 500W..." part of the answer. – Móż Oct 19 '15 at 20:52
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    I added a torque arm and it is working perfectly now. I feel so much safer. Thank you all for your suggestions and especially renesis for the torque arm suggestion which I used...!!! – user22796 Oct 21 '15 at 20:30

Yes - one or two torque arms will help. Otherwise all the impulse is being send through your dropouts, which will be steel and will flex. This undoes the wheel nuts over time. This also fretts out the dropouts whih will cost you a new fork.

Do you have anti-rotation washers in the fork dropouts too? Even my 250W motor needed them.

More info: enter image description here

From http://www.ebikeschool.com/torque-arm-need-one/

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    Thanks Criggie...and best of all it worked...!!! Now I can ride my bike with confidence. Thanks for your help in the wiring and battery questions I had also... – user22796 Oct 21 '15 at 20:33

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