Help! Bafang kit fitted, pedal stripped thread.

Encantador

Pedelecer
Jul 18, 2008
76
5
Hi,

I recently fitted BBS02 kit to my old Trek Hybrid, I used the crank arms that came with the kit.

I did have a problem fitting new pedals with one pair from Amazon refusing to work, I could not get the thread to start. As someone in the reviews had mentioned the same problem, I decided it was the pedal and purchased a different pedal (this may be totally irrelevant to my problem).

Today I rode it for the first time in a few days, have covered about 50 miles since conversion. Today my right pedal felt weird, cant put my finger on it but just not right. I stopped a couple of times to take a look and everything looked normal.

Pulling away at lights my right pedal fell to the floor, could have been dangerous.

Obviously, need new arms and pedals just wondering if anyone can shed any light on what might have caused it. Purchased the kit through Amazon from a respected seller and no reviews had mentioned any problems with the quality of the crank arms.

Any suggestions on the cause would be useful.

Thanks

Steve
 

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vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,944
Basildon
That happens when you don't fully tighten the pedal in the arm. It has be pretty tight otherwise there's a microscopic amount of movement in the thread, As you keep pedalling, the movement wears the thread, making it looser and looser until the thread is insufficient to hold the pedal in, then the pedal falls out, leaving you stranded.

The pedal has a hardened steel thread, so should still be OK, but your arm is scrap.
 
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Encantador

Pedelecer
Jul 18, 2008
76
5
Thanks for the reply. Glad to know it was me (in a way) and not the kit. I have just put the original crank back on for now. The pedal thread is slightly damaged so I will replace it too.

Thanks again.

Steve
 

cyclebuddy

Esteemed Pedelecer
Nov 2, 2016
843
425
Beds & Norfolk
Pedals are stamped R (right hand) and L (left hand). One is a clockwise thread, the other counter clockwise. If you put them in in reverse, the thread undoes and the pedal falls off. If you put them in correctly, the action of pedalling actually tightens the thread, not undoes it.
 

jokskot

Pedelecer
Jul 14, 2018
115
43
73
Pedals are stamped R (right hand) and L (left hand). One is a clockwise thread, the other counter clockwise. If you put them in in reverse, the thread undoes and the pedal falls off. If you put them in correctly, the action of pedalling actually tightens the thread, not undoes it.
Agree except in my experience you can't put them in incorrectly unless you use brute force and completely strip the threads