2500 mile update-Pedal of shame/ time for new torque arms

V

Voltron

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So, after many high throttle miles, my slapped together open end wrench "temporary" torque arms finally got loose enough to let the axle spin, letting the tire hit the frame and twisting the wires until it cut out. That's complacency for you...

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Anyway, that made it time to make some torque arms. This is for a Yuba Mundo, which has 14mm dropouts, but the motor has 12 mm flats. Started out with an aluminum bar cutoff from the scrap pile, then started milling it from both ends but leaving a clamping area in the middle, then some drilling.

KIMG02371.jpg

Then a little fine tuning on the fit with a hand file, and cutting them off the bar with a band saw, and there's some torque arms for you.

 
There's a thin rib to take up the space between the dropout and the axle.



The left over center section...

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Contured around the deraileur and brake...


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baling wire and duct tape keeps us rolling.jpg
 
That wire is what was holding on my wrenches too... And wasn't what failed.
It's actually Monel stainless seizing wire for sailboats. A little pricy for baling hay.. :D

KIMG02471_2.jpg

Went for a little shakedown run up the mountain...
 
Since you made a slide on tourque arm could you sale them. I wanna run 2 torque arms but just am way to lazy to cut my wires and solder them back on to add the closed tourque arms being sole everywhere.
 
Should have made that in steel. Well, if it lasted with a wrench and wire, it will do in Alu for some time I guess. :wink:
 
MadRhino said:
Should have made that in steel. Well, if it lasted with a wrench and wire, it will do in Alu for some time I guess. :wink:
Click to expand...

+1

Even though they're brand new, it's already time for new torque arms, because that isn't safe.
 
With the moderate power level and no regen rocking the axle both ways I think it will be ok. If it looks like the flats are getting any wear after a while it will be easy to copy these in steel now that the shape is right.
 
It could've been worse :lol: :oops: :
https://endless-sphere.com/forums/viewtopic.php?f=2&t=22720&hilit=delta+tripper+fell+off&start=100#p725069
file.php
 
A better solution would be

1) use a better bike with full suspension, you'll thank yourself, THEN replace the swingarm with
2) custom swingarm with purpose built lockdown dropouts ($200 and a phone call to your local welder / fabricator away)
 
Well, for burning up the paved canyon roads where I'm at, the hard tail does just fine. I have a couple of other full suspensions, but there's something special about the way this one rides.

That being said, I am working at a welder/ fabricator shop now.... so custom swingarms are in the pipeline now on a couple of other projects.
 
Finally had to get into the hub for some brake work.....and here's the torque arms after about 2500 miles. I'd say it looks like they're holding up pretty well.

ta right.jpg
ta left.jpg
 
MadRhino said:
Should have made that in steel. Well, if it lasted with a wrench and wire, it will do in Alu for some time I guess. :wink:
Click to expand...
The last torque arm I made was from 7050 aluminum, which is about the same strength as normalized 4130 chromoly. The material is much easier to machine than steel, too, which is why I made the torque arm 10mm thick. I have no doubt it is stronger and more secure than a 5-6mm thick steel torque arm, and also much less likely to damage the axle threads.
 
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