Near fail experience, Dropouts

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samoloh   10 W

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Near fail experience, Dropouts

Post by samoloh » Sep 11 2013 7:51pm

I would usually lift my rear wheel the ground and do full throttle just for fun, I was doing the same thing today when as soon as i started i heard grinding sounds, i thot i had damaged my motor, but on closer examination I found my axle was on the verge of spinning out :shock:

I recalled that the previous day i did some light trail riding (nothing rough), might have hit a few bumps here and there, but then i realized i hadn't for once re-tightened my nuts since i started riding, buts its been only a week anyway. The max power i've ever draw is about 800+ watts. Do I just need to check my nuts more often or get a torque arm?
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chrashing   100 mW

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Re: Near fail experience, Dropouts

Post by chrashing » Sep 11 2013 7:54pm

Glad you caught that, thanks for the heads up. Will check mine.

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amberwolf   100 GW

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Re: Near fail experience, Dropouts

Post by amberwolf » Sep 11 2013 8:10pm

i'd use torque arms regardless, just to help protect the wheel from falling out if hte dropouts did fail...and also to keep the dropouts from having to do a job they're not usually designed for in the first place. ;)

but to keep the nuts tight, you can get Nord Lock washers--there's some in the for sale section now, I think.

captain387   100 W

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Re: Near fail experience, Dropouts

Post by captain387 » Sep 11 2013 8:13pm

Torque arms, with Nord lock washers are a must.
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pdf   10 kW

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Re: Near fail experience, Dropouts

Post by pdf » Sep 11 2013 8:18pm

Torque arms, for sure. You can't get the axle nuts tight enough. I have found that axles that fit tightly in the dropouts (that is, larger axles) tend to spin out less easily than smaller diameter axles, but when the dropouts are spread a little, you are sure to spin the axle if you don't add a torque arm.
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Drunkskunk   100 GW

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Re: Near fail experience, Dropouts

Post by Drunkskunk » Sep 11 2013 9:49pm

This is a great example of why you need protection all the time. You were riding her nice and easy, not putting your weight on her at all, but you unexpectedly lost tension on your nuts. Lucky for you, it just fell out of her slot before any damage was done, but that could have been the kind of accident that ruins things forever.

Oh, wait. We're talking about bikes. Eh, same thing. Use protection, and double up if you can.

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Last edited by Drunkskunk on Sep 12 2013 3:32am, edited 1 time in total.
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d8veh   100 GW

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Re: Near fail experience, Dropouts

Post by d8veh » Sep 12 2013 3:30am

It looks to me like your installation could be improved. Normally the anti-rotation washers go on the inside of the drop-out and the plain washer on the outside. For most people that's not important, but in your photo it looks like you have a dimple around the drop-out. The large anti-rotation washer will be off-centre to the dimple o t'll sit crooked and work loose in operation. If you have a dimple, the first washer must sit completely within it, which means either you have to file the drop-outs deeper to re-centralise the axle, or file the washer eccentric. I normally file the drop-outs so that the anti-rotation washer can do its job instead of sitting out in the air.

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dogman dan   100 GW

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Re: Near fail experience, Dropouts

Post by dogman dan » Sep 12 2013 7:07am

No, it's the lack of torque plates. You might have to make some custom ones for that bike.

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GCinDC   10 GW

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Re: Near fail experience, Dropouts

Post by GCinDC » Sep 12 2013 7:15am

go to and scroll all the way down to the section: Rear Torque Arms...
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