Pedal sheered from crank on SRAM Apex

by SB76   April 18, 2014  

Anyone any thoughts on this. I've got a 6 month old East R2 and today about 25 miles into a 40 miler I noticed movement on my right foot. I stopped to check my cleat but that was fine and on further inspection, I noticed the pedal had worked itself loose. I quickly screwed it back in but within a few meters, it was loose again.
I took the pedal out and noticed the crank thread was totally shot!

I do give the bike a regular check over prior to going out and hadn't noticed anything. Interestingly, I'd had it in for a free service only a week ago!

Incorrectly installed pedal or thread pedal maybe?

8 user comments

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Most likely like it just came loose and riding it has damaged the thread. I think you'll find it hard to pin on the shop unless pedals were included in the service.

Sound like a new crank arm is required, probably not economic to try and repair it.

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posted by joemmo [774 posts]
18th April 2014 - 19:06

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I took it straight into the shop, they seemed baffled. The bike comes with very good warranty on the parts and he was convinced it'll be replaced free anyway. A little more suspicious myself as I think it was down to usage when probably it shouldn't have been.

More it's a case of being keen for it not to happen again. I was only playing with the pedal, two days ago and it wasn't wobbling ( didn't screw/ unscrew it mind). The only ting that annoys me with the service, was I know the messed about with the chain so if the pedal was problematic, I'd hope they'd have spotted it and saved me money probably and more importantly I wouldn't lose a weeks riding time!!

The key thing is, I don't want it to happen in another 6 months and hence the question over trying to blame the shop and hence the query.

posted by SB76 [80 posts]
18th April 2014 - 19:58

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The reason pedals are threaded in opposite directions is that it means that when you ride them they tend to tighten rather than loosen. I suspect ham fisted mechanic somewhere down the line (although I guess its possible that there was a manufacturing weaknesses of some sort, seems unlikely though).

posted by racingcondor [109 posts]
18th April 2014 - 21:20

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Just gutted, had a busy weekend of cycling planned.

posted by SB76 [80 posts]
18th April 2014 - 21:30

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It is possible to get thread repair kits for certain thread sizes, but I doubt very much that there would be enough material to repair the crank given the thickness of crank arms, even if you could find a repair kit of the correct size/thread-handedness.

Unfortunately a new crank/pedal is likely to be the solution.

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posted by lisa76uk [26 posts]
18th April 2014 - 23:39

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I've just asked for a new crank. The pedal thread is in perfect condition. The shop said they've only seen this if the pedal was wrong for the crank.

posted by SB76 [80 posts]
19th April 2014 - 8:01

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SB76 wrote:
I've just asked for a new crank. The pedal thread is in perfect condition. The shop said they've only seen this if the pedal was wrong for the crank.

That's the solution.

The pedal threads are fine as (I'm assuming) theyre steel and therefore in a scissors paper stone type way have eaten the softer alloy threads of the crank arm. This can happen shockingly quickly if a pedal is insufficiently torqued up...

Usually when first installed or at a service... Which is the root cause.

The bike shop statement about pedal being wrong for the crank is unashamed Bollox.

My eyes prefer Celeste, my bum prefers titanium.

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posted by Jack Osbourne snr [304 posts]
19th April 2014 - 10:11

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The problem with alloys I guess. Yes, it smells a little but unfortunate mistake

posted by SB76 [80 posts]
19th April 2014 - 10:53

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