Pedal strike - Bent pedal axle, bent crank arm, or both?

John U

John U

MTB Precision
Howdy Burners,
I've been smashing pedals since I was a 10 year old bmxer. Recent circumstances had me doing a bit of investigating which indicated that riding with bent axles isn't a good idea. So while I was waiting for a new derailleur, and hanger, post a recent commuting mishap, I also decided to get new pedals. All parts fitted to the commuter, and take off for it's maiden voyage yesterday and fuck me, that pedal still feels bent.

Pedal is one of those crank bros cross over clip in/flat. Unless they are shipping them pre-bent, the issue appears to be with my crank arm (Shimano 105 from about 2019). I guess the crank arm is alloy so it makes sense?

The stack I had which caused the issue was a low speed front wheel wash out on bitumen. I went down pretty hard but minimal gravel rash.

Getting to the point, with a pedal strike of any sort is the crank arm more likely to incur the damage, or the pedal axle, or is it both? Given that there's different materials involved.

I have many 'bent pedals' on my bikes, which as recently found I should resolve.
 
Grab a 6mm hex, put it in a battery drill then lock the pedal body in a vise. Insert 6mm hex bit into pedal tightening hex hole and give err a full speed run and feel whats happening, if you cant spin it straight without wobbling the drill, its a spindle. Take the pedal out and hold it in your hand, give it another full speed blast and feel the possible wobble, if the pedal no wobbles, its a bent pedal. You'll be able to work out by doing both of these if its either the pedal or the spindle, or maybe both.
 
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John U said:
Getting to the point, with a pedal strike of any sort is the crank arm more likely to incur the damage, or the pedal axle, or is it both? Given that there's different materials involved.
Click to expand...

I've bent cranks before without bending the pedal axle, in a similar manner to the crash you described. If the brand new pedals feel bent, then it's more than likely your crank arm
 
John U said:
Howdy Burners,
I've been smashing pedals since I was a 10 year old bmxer. Recent circumstances had me doing a bit of investigating which indicated that riding with bent axles isn't a good idea. So while I was waiting for a new derailleur, and hanger, post a recent commuting mishap, I also decided to get new pedals. All parts fitted to the commuter, and take off for it's maiden voyage yesterday and fuck me, that pedal still feels bent.

Pedal is one of those crank bros cross over clip in/flat. Unless they are shipping them pre-bent, the issue appears to be with my crank arm (Shimano 105 from about 2019). I guess the crank arm is alloy so it makes sense?

The stack I had which caused the issue was a low speed front wheel wash out on bitumen. I went down pretty hard but minimal gravel rash.

Getting to the point, with a pedal strike of any sort is the crank arm more likely to incur the damage, or the pedal axle, or is it both? Given that there's different materials involved.

I have many 'bent pedals' on my bikes, which as recently found I should resolve.
Click to expand...
If your knees and ankles have gotten used to a bent pedal, it's also possible that a non-bent pedal will consequently feel 'bent'.
Could be worth popping the cranks off and seeing if the hollowtech II axle is buggered.
Was the pedal strike on the drive side or the LHS?
 
ForkinGreat said:
If your knees and ankles have gotten used to a bent pedal, it's also possible that a non-bent pedal will consequently feel 'bent'.
Could be worth popping the cranks off and seeing if the hollowtech II axle is buggered.
Was the pedal strike on the drive side or the LHS?
Click to expand...
Drive side.

Having multiple bikes with varying bentness hopefully reduces the bent feel factor.

I reckon I've been riding with bent pedals or cranks on and off for my entire riding life. I used to rip the ends off those pressed metal bmx pedals every other week in the 80's. At $5 or $6 a set it resulted in my mum forking out the insane amount of about $30 for the original pinned flat pedal, the Shimano DX, which never needed to be replaced but chewed the shit out of my thongs.

I used egg beaters on all my bikes for quite a few years. Being a bit smaller/having less surface area might've actually made them a bit less likely to get bent. Moving back to flat/flat clip ins might've brought all that bent goodness back with it.

I'll go all in and buy a new crankset and find out if it's the cranks or the pedal axles that are made of cheese.

Wish me luck. About to launch into the world of constantly changing standards.

yuley95 said:
New leg time!
Click to expand...
If only. Can you hook me up?
 
Staunch said:
I've bent cranks before without bending the pedal axle, in a similar manner to the crash you described. If the brand new pedals feel bent, then it's more than likely your crank arm
Click to expand...
I'd go with this; almost certainly a bent or twisted crank. Pedal axles are relatively short, so need a big force to bend them. Cranks are longer, so a given impact force has more leverage to cause deformation to the crank.

I've seen numerous cranks twisted from the mounting on shuttling trailers - ironically mostly on Eeebs!
 
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