Are Torque Arms necessary for my electric bike conversion kit?
The short answer is yes.
For those that don’t know what torque arms are, they are usually a small plate of metal that goes over the axle they have flat edges to match the axle then they are bolted (or hose clamped ) onto the frame or forks of your bike. They prevent the axle spinning in the drop outs. In some cases the axle spinning might just cause a little wear in the drop outs or bend open the drop outs a little which could get a little dangerous. Where the main problem lies is if you are using alloy forks with a high power motor as alloy has the tenancy to crack meaning your front wheel could suddenly end up falling off … giving your face a close encounter with the road.
With steel forks and a small to mid sized motor you will probably be fine without torque arms.
With alloy forks and a small motor and the nuts regularly checked you may be OK but you’re still taking a risk.
With alloy Forks and high power motors you are likely to have the forks fail leading to catastrophic consequences.
So unless you have a low powered motor and steel forks it is well worth the $10 or so to get a torque arm and know you are safe. This can also save unnecessary wear on the drop outs of your bike.
Most e-bike kit sellers have torque arms for sale, otherwise I’m sure there will be something on ebay.