Giant DH Comp - Damageless Torque Arms…

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Bison_69   100 W

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Giant DH Comp - Damageless Torque Arms…

Post by Bison_69 » Sep 17 2011 8:15am

Hi guys,

Here is the torque-arms I am using on my bike… the idea of this kit is being able to use the frame back in its original shape (prevent unwanted stress on the structure) also if for some reason you decide one day to sell your bike or buy a better one…

I designed all the torque-arm parts with SolidWorks and the parts were made to a local machine shop (laser cut). The alloy used was QT-100 and Domex-100 very strong steel.

Inside width for wheel 140mm. Fasteners are from McMaster stainless steel (hi-grade).

(see enclosed pictures and data)
Domex 100 W.pdf
Alloy Spec sheet
(189.2 KiB) Downloaded 293 times
Rear hub motor & torque arm exploded view.jpg
Hub motor and torque arm
Rear hub motor & torque arm exploded view.jpg (64.82 KiB) Viewed 468 times
Hub motor and torque arm installed on swing arm
DSCN1952_.JPG (184.72 KiB) Viewed 468 times
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voicecoils   10 MW

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Re: Giant DH Comp - Damageless Torque Arms…

Post by voicecoils » Sep 17 2011 8:45am

Awesome job!

Do you plan to release the CAD files so others can have parts locally lasercut?

How are you positioning the brake calliper with the wheel in the new lower position, below the original axle?

whereswally606   100 kW

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Re: Giant DH Comp - Damageless Torque Arms…

Post by whereswally606 » Sep 17 2011 1:46pm

very nice work. I though about doing something similar on my 1000w gm scott ransom 30 alu build. In the end I bought the IDS (interchangable drop out/frame savers) and machined them to fit the hub motor axle so it would sit deep enough in the gap. I think ive been ok up to now as im at 48v though im planning to take it up to 72v soon with a hua tong (cheap £20 generic) controller. That said i dont wanna have an accident when i do do this. I definately dont want the IDS to crack. On my other build i put some dr bass torque arms. Its a cheap steel one so ive not issues with fixing them on permanently.

Really like the design, very slick.

regards Andy
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