Torque Arm Mounting???

[rogerc]

Okay here goes, have to ask this even though I think I know the answer and will get some dumb looks from you guru's.

I purchased a version 4 torque arm Grim Tech and due to a rear rack installed on the bike it does not fit and I need the rack for my bike design.
Is it mandatory that the torque arm be attached by the hose clamp to the frame of the bike or can I attach it to the frame of my rack?
It is a heavy duty metal frame rack and is bolted into the frame in the usual spot for rear frames on bikes.
Running a mac 10 motor at 54v with 25 amps.

I know attaching it to the frame is the best and safest but I am willingly to comprise a little and attach to the rear rack to get the design I want.
Is it totally unsafe or just not as safe. I am 60 years old and not a speed demon anymore, I have a Ducati for that.

Okay guys you can start calling me names...
RC

 

[footloose]

Hi Roger,

Not a guru by any means, but attaching torque arm to the bike rack doesn't sound like a red hot idea.
Even with a stainless steel Tubus frame, the individual rack members probably aren't hugely strong in their own right... the entire rack becomes very strong when they are all welded together, but you'd be attaching to just one of them and my guess is it could deform pretty easily.

You sure the normal attachment can't work? Possible to include photos of frame, rack? You might get some creative suggestions on how to do it if folks could see exact situation.

Steve

PS -- finish it up and let's go for a ride before the rains start!

 

[crezzy2k1]

Not sure about doing that mate. I have a 36v battery on my rear rack and I've noticed it stripped the screw threads in the frame due to the weight.

 

[mlt34]

Best to avoid the rack members. Can you post some pics of your situation and we can put our heads together to find a solution. The solution already exists, we just have to find it...

 

[dogman dan]

Name calling not allowed if I see it. We might call your ideas names though. Just don't call people names.

We'd need pictures of the situation to say much helpful.

Bottom line though, you must install the torque arm properly. Then, the next step is to figure out which modification to your rack, or different rack will work.

LOTS of different options with the rack. It's not mandatory that it attach to the lugs on the frame. Other methods exist. One obvious option is to make a metal plate that adapts the rack to attach to the axle itself. The next obvious one would be some kind of clamps to the chain stay setup, but that may or may not be strong enough depending on the situation.

A seatpost rack can be very strong, when you add a set of homemade legs to it. The legs diagonal back to attach low on the seatpost tube of the frame.