Alternate Crank set and pedals

Out of pure curiosity, wondering what's happening to your crank set and pedals that's causing you to replace them?
 
Out of pure curiosity, wondering what's happening to your crank set and pedals that's causing you to replace them?

Hey Hicks, I have no clue. I can't imagine I pedal any differently than anyone else. I weigh about 176 lbs and I ride to work any day it's not raining, on a windy and slightly hilly bike trail. The only thing I can think of is that it's my dominant leg, and maybe I'm pressing in a different angle on the pedal with more force, I have no clue.

Or for whatever reason maybe I've received 2 defective batches.
 
So you're bending them?

I doubt it's your weight. I'm over 300 and not having any trouble...
 
Is it just the pedals causing the issue? I'm a little under 300lbs when fully decked out for work commuting with winter gear and commuter backpack. Seems like the aluminum crank seems pretty standard for a lot bike and ebikes? I upgraded my pedals to BC extra wide platform MTB pedals. I found the Radrover pedals were too small for my size 14 feet and they sometimes slip off when trail riding (especially in wetter conditions). Zero issues with slipping, solid aluminum design, and I have plenty of grip with any type of shoes I wearing at the time. Most I have to do with these pedals is apply a little touch-up paint every once in while.

About $80 on Amazon: https://www.amazon.com/Platform-Mou...r=8-2-fkmr1&keywords=bc+mtb+extra+wide+pedals

I found for around $62 on eBay: (Link Removed - No Longer Exists)
 
Somehow the threads keep stripping. I mean, they only thread in one way and I cranked them down flush. Take a look.
 

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Those pedals are severely cross threaded. You started them crooked, and all those metal bits you see there are the threads torn out. When they are crooked to the face of the crank, you did it wrong and they are destroyed. You should be able to thread the pedals nearly all the way in WITHOUT a wrench and with little effort. If it takes effort and a wrench to get them started, it's crooked! I'd suggest you take it to a bicycle shop for the repair if you've done this twice already.
 
Is it just the pedals causing the issue? I'm a little under 300lbs when fully decked out for work commuting with winter gear and commuter backpack. Seems like the aluminum crank seems pretty standard for a lot bike and ebikes? I upgraded my pedals to BC extra wide platform MTB pedals. I found the Radrover pedals were too small for my size 14 feet and they sometimes slip off when trail riding (especially in wetter conditions). Zero issues with slipping, solid aluminum design, and I have plenty of grip with any type of shoes I wearing at the time. Most I have to do with these pedals is apply a little touch-up paint every once in while.

About $80 on Amazon: https://www.amazon.com/Platform-Mou...r=8-2-fkmr1&keywords=bc+mtb+extra+wide+pedals

I found for around $62 on eBay: (Link Removed - No Longer Exists)

Thank you.
 
Those pedals are severely cross threaded. You started them crooked, and all those metal bits you see there are the threads torn out. When they are crooked to the face of the crank, you did it wrong and they are destroyed. You should be able to thread the pedals nearly all the way in WITHOUT a wrench and with little effort. If it takes effort and a wrench to get them started, it's crooked! I'd suggest you take it to a bicycle shop for the repair if you've done this twice already.

They're cross threaded, because it came loose while riding, and I had no choice but to force them back in when I got to work or else it would have fallen out.

I knew they would get destroyed when putting them back in but I had no choice, as I needed to get home. Yes, I fed it in by hand and used a wrench at the end. I wasn't forcing anything. They were flush.
And if that was the case, then why would it only be on one side? My left pedal was installed the same way, same resistance, etc, and it's fine, it's the original.

The first time they were damaged because the bike fell. I made sure they knew that and they replaced it, no problem.
 
You're making me think I should go out and check mine. I've never had that issue before (a pedal coming out after original install) but you're the absolute proof anything is possible!
 
The most common cause of crank's pedal thread stripping is over-tightening. Pedals should be tightened very lightly as you may want to change them from time to time. It is safe to tighten them lightly as the directional thread tightens naturally with your pedaling.

The pedal axle/spindle is steel and the crank is usually aluminum alloy...much softer so it is also a good idea to put a little grease on the threads before threading them in.
 
One side is right thread, one side is left thread, is that the problem? Pedals are made for a certain side.
 
What kind of wrench are you using to secure the pedals to the crank arm? Even though pedals are threaded in such a way as to promote them staying on, pedals need to be tightened properly from the get-go. Shimano recommends a minimum of 35 Nm of torque. If you use a small wrench, like a 6" adjustable "Crescent" wrench, you need to tighten down hard to get to that amount of torque.
 
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The most common cause of crank's pedal thread stripping is over-tightening. Pedals should be tightened very lightly as you may want to change them from time to time. It is safe to tighten them lightly as the directional thread tightens naturally with your pedaling.

The pedal axle/spindle is steel and the crank is usually aluminum alloy...much softer so it is also a good idea to put a little grease on the threads before threading them in.
True...the very idea of pedals loosening against their threading seems not possible. I've got road pedals coming with toe clips, and I just unthreaded mine to be sure they weren't too tight. They weren't, and of course I had greased them. Never-Seez next time, as on the crank bolts.
 
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Somehow the threads keep stripping. I mean, they only thread in one way and I cranked them down flush. Take a look.
Yes, crank arms are shot...Since they're aluminum, they get the damage. I'd never trust a repair, if it's even possible...replace...they're cheap enough.
 
I don't think I'd order an extra set of arms. Pretty unusual for you to need the fist set....
 
The strength of a threaded joint like that is really the face of the joint. The thread is there to keep it faces tight to each other. If the faces lose hard contact, the full load then goes through the threads. The cheap aluminum alloys used in the cranks will not survive that loose joint. I disagree that the most common thread failure is from over tightening, but instead not maintaining proper tightening. A good description; https://bicycles.stackexchange.com/questions/54167/why-does-a-loose-pedal-destroy-the-crank-threads
 
Agree totally.
My note was in response to his original note, wondering if he needed to keep an extra pair on hand.
 
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