Can someone double check my torque arm installation?

That link doesn't work right. Take off the IMG brackets so it will show as a hyperlink.

Anyway, it looks OK to me, as long as everything is nice and tight. What's the maximum torque of your motor?
 
Thanks for the heads up, I attached a pic directly.
I am using a 1000W ebay hub motor with a 14s battery on a Trek 4500 aluminum frame. I probably will stay at 25mph or less.

It is a grintec v4 torque arm. I tried installing another on the opposite side, but the arm hits the bolt that holds on the disc brakes. I may try and find a different torque arm for the other side if it is necessary.
 
transposon said:
It is a grintec v4 torque arm. I tried installing another on the opposite side, but the arm hits the bolt that holds on the disc brakes. I may try and find a different torque arm for the other side if it is necessary.

Can you post a pic of the problem side and how the torque arm interferes with the caliper bolts?

There may be a way to fabricate something. For mine, I bolted on a plate with longer caliper bolts, then drilled and tapped the plate to fix the torque arm to:
https://endless-sphere.com/forums/viewtopic.php?f=6&t=97945#p1451659

I have a cheap generic one on the other side, mainly set up to handle regen.
 
Picture looks correct to me.
 
try rotating it 180 degrees

EDIT: looks like it just clears the frame (actually might be nice if it touches and supported by it). If it doesn't, it can be flipped and definitely clear it.
torque arm 180.jpg
 
yup. point it down.
 


I thought about that, but given the direction of wheel rotation and the fact that the arm would be held on by hose clamps, wouldn't it not do much to resist the axle rotating? It seems to me that the outer arm would just slide down the frame.
 
transposon said:
I thought about that, but given the direction of wheel rotation and the fact that the arm would be held on by hose clamps, wouldn't it not do much to resist the axle rotating? It seems to me that the outer arm would just slide down the frame.

To me it looks about as good as it gets.
 
transposon said:
I thought about that, but given the direction of wheel rotation and the fact that the arm would be held on by hose clamps, wouldn't it not do much to resist the axle rotating? It seems to me that the outer arm would just slide down the frame.

I've used that torque arm in that configuration on a few bikes over the last few years. It's never been a problem, even on a build where I was running 1800w peaks + some light regen. Just make sure to tighten everything down properly and it should be fine.
 
They'll all work, but if I could make it happen easy enough, I would ditch the second part of the arm, and try to find a place where it lines up with a bolt hole in the frame already (even if it means a little hammer therapy, the steel arm can take some pre deformation without failing), or drill one in the middle of the dropout casting somewhere. It makes so many less parts to deal with.
Sometimes spacer-ing it out from the frame gets more important, as those other parts soak up some misalignment.
 
I'd even consider sawing off the slotted section, and drilling a hole in the plate that's left... It really doesn't need that long of a lever arm when it's bolted to the frame, and with the 3d cast dropouts you have, you might even be able to cut it right to nestle in there nice and flat everywhere. The important thing is the axle slot fitting tight, the rest can be a little rough around the edges if you know what I mean...
 
On a different note, is that as far as the axle goes into the dropouts? Usually you have to file a bit off the frame to get a hub motor axle up in there far enough, which you would want to do before going crazy on the perfect torque arm, as it might move the holes needed. Besides trying to pry open the dropout more, it makes the brake rotor ride low, so the pads don't grab as much, and they get a lip above where the rotor is now that makes them wear fast when the pads start touching in the middle over the rotor.
 
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