Trek 7.2 FX Frame?

[blk-c6]

I just recently picked up a Trek 7.2 FX Hybrid bike that I'm planning to convert to an eBike. From what I read on the Trek site, it has a steel front fork.
Would it be ok to run a front hub motor like the AmpedBikes.com motor without having to worry about getting torque arms? I'm planning on running it
at the normal 36v.

Thanks!

 

[broloch]

Your fork will fail -it is NOT a matter of if, but WHEN. So, do get torque arms, especially if you have a front motor. It might be fatal, or very dangerous if something goes wrong in the front. One dude, snapped both of his collar bones. If you like your collar bones...

 

[deecanio]

HI,

yes don't mess about with front mounting - for a few dollars you can make up some arms which will save you from a large inevitable face plant, rather pay out for arms than new teeth.


cheers


D

 

[CGameProgrammer]

My first e-bike used a Trek 7.2 FX. I did not use torque arms and I broke the fork and the motor very quickly. Granted, this was largely due to not making the nuts anywhere near tight enough, but you definitely will need a torque arm as well.

 

[Drunkskunk]

4200 pounds of pressure
Thats roughly how much force the motor is applying to the dropouts every time you hit the throttle from a standstill. 4200 pounds of torque twisting against 1/4 inch of metal. its not a question of If it will fail, but when.

Welcome to the forum. Thats a good price on the kit. the motor is a golden motor, I know a few here use them and are happy with them.