Need torque arm advice

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vodk1c3   100 W

100 W
Posts: 100
Joined: Jul 27 2012 2:49am
Location: Québec, Canada

Need torque arm advice

Post by vodk1c3 » Jul 28 2012 4:32am

Hi everyone,

I PM'ed doctorbass today about torque arm but he mentioned in the thread not to put our project on hold till the next torque arm batch.
Kit is rear wheel china made and bike is a cheap steel frame, 1200w 48v / 12ah lifepo4.
I did a couple of run without torque arm and it was AWESOME. But now the dropout are spread and the nut on the axle don't turn very well even stuck at some point. :( :(
What would be your next move?? bend back dropout?? powertool the nut out??? try to make a homemade torque arm??
Witch torque arm design would be easiest without alot of tool (what thickness!?!) ?? Can I use torque arm on a spread dropout??
Is it as simple as choosing a good plate and using a hacksaw and a drill???

Thanks guys, this forum is sooooo usefull for noob like me 8)
First bike (Nitro XT) :
Vpower 1000w 48v 26" rear kit
Vpower LiFePo4 48v 12a battery / 5a charger
20km+@35km/h | 45km/h max speed

Second bike (Everything working, snow is fun ^^) :
Crystalyte HS3540 24" rear
25s1p 5000mah LiPo @ 100v / iMaxb6 charger / Hua tong 72v 35a instant start controller
65+ km/h and lot of torque; battery sag alot; http://www.youtube.com/watch?v=nqf8drRaj9k


Currently working on my first high power build with DH frame / A123 pouch

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dogman dan   100 GW

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Joined: May 17 2008 12:53pm
Location: Las Cruces New Mexico USA

Re: Need torque arm advice

Post by dogman dan » Jul 28 2012 5:37am

Likely you can bend the dropout of a cheap steel bike back once. Then you need torque arms. Make some from 1/4" steel plate, or buy some universal rear arms from Grin.

A pinch dropout is easy on steel, weld on a piece of angle iron, then bolt to pinch the axle.
Pinch dropout, on Race bike..jpg
Pinch dropout, on Race bike..jpg (90.59 KiB) Viewed 406 times
Hopefully you can save the threads on the axle, and get new nuts the right size. If not, then a pinch setup might be your only option.

SoSauty   1 kW

1 kW
Posts: 339
Joined: Mar 17 2009 11:40pm

Re: Need torque arm advice

Post by SoSauty » Jul 28 2012 3:13pm

Well well, happen to have an extra Grin torque arm. I ordered 2 and the idea of 'modding my wide 150mm Chinese bike drop out area' came to fruation.

Check your PM.
Will

Dogmanz, now that's a functional racing 9C drop out :!:

And check the 2 Stroke E-chaser thread, http://www.endless-sphere.com/forums/vi ... =3&t=41959

I'm going against every grain of advice you gave me, awkward to explain but should make sense in the end :?
http://www.ebikes.ca/index.shtml No.#1 Trusted E-bike online sales!
3 hardtail MTBs:
-48V Lith-ion 10.5amp hr-408 C-lyte
-BPM 8FUN[*STOLEN]
-run Century rides w/Q100 mini
3 folders:
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-24" Stewart/Hass 9C; 3.5K/40mph fun racer

MikeFairbanks   100 kW

100 kW
Posts: 1389
Joined: Mar 09 2010 6:23pm
Location: Atlanta, Georgia, USA

Re: Need torque arm advice

Post by MikeFairbanks » Jul 28 2012 3:47pm

A great make-do torque arm is a small crescent wrench. Find one that perfectly fits the axle and attach it to the frame using the same clamps you would with a regular torque arm. It works like a charm.
Stay frosty

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vodk1c3   100 W

100 W
Posts: 100
Joined: Jul 27 2012 2:49am
Location: Québec, Canada

Re: Need torque arm advice

Post by vodk1c3 » Jul 28 2012 6:29pm

I will try to cut some galvanized steel plate I found at Rona, wish me luck ^^
Those plates are really nice because they already have a 10mm hole that fit exactly the axle.

dogman : Idea of a pinch dropout is really really nice if my bolt fail!!!!

SoSauty : wow thanks man!!! I will gladly take em if homemade way fail ! I like your E-chaser custom dropout!

MikeFairbanks : maybe an option, ill have to test it

Thanks alot guys wasn't expecting 3 answers and a free pair of torque arm in the same day :D :D
First time I see such a supportive community on the web, keep up the good work!

-vodk1c3
First bike (Nitro XT) :
Vpower 1000w 48v 26" rear kit
Vpower LiFePo4 48v 12a battery / 5a charger
20km+@35km/h | 45km/h max speed

Second bike (Everything working, snow is fun ^^) :
Crystalyte HS3540 24" rear
25s1p 5000mah LiPo @ 100v / iMaxb6 charger / Hua tong 72v 35a instant start controller
65+ km/h and lot of torque; battery sag alot; http://www.youtube.com/watch?v=nqf8drRaj9k


Currently working on my first high power build with DH frame / A123 pouch

aroundqube   1 kW

1 kW
Posts: 464
Joined: Mar 12 2012 9:58pm

Re: Need torque arm advice

Post by aroundqube » Jul 28 2012 11:09pm

MikeFairbanks wrote:A great make-do torque arm is a small crescent wrench. Find one that perfectly fits the axle and attach it to the frame using the same clamps you would with a regular torque arm. It works like a charm.
Did you mean open end wrench? Crescent is a brand name associated with an adjustable wrench,which will not maintain a fixed opening size.

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