Need Help! crank thread issue

[Theboyjamin]

Hi guys I'm not the most tech guy when it comes to bikes so this might be a easy fix or might not was riding along today and my peddle started to come loose/come off once got home realised the peddle has shredded the crank arm thread where the peddle goes into? this is my first time on the bike so I'm guessing i have done something wrong when putting it together yesterday? so gutted!!

hope someone can help thank you guys!

 

[boBE]

There are helicoil type repair kits for stripped crank arms. They are usually $$$ because of the special taps (one is left hand). Your local bike shop is likely to have one.
It may cost less to buy a new crank arm.

 

[Shy Ted]

Agree, new crank, but looks like there’s no grease on the pedal thread, which you definitely need. Might be cost effective to let the LBS do it as you’ll probably need a crank puller to do it. If the pedal thread is stripped then get new pedals too, you don’t want to be stripping the new crank thread.

 

[RoJo]

New cranks I'm afraid (and new pedal). The Shimano cranks are not too hard to fit if you follow the instructions. Worth buying a torque wrench from Toolstation/Screwfix.

STEPS FC-E8000 Crank Arm Set without Chainring

Visually a real looker, smooth and comfortable to function. Even under high strain, the crank is stiff and therefore provides good support. SHIMANO STEPS MTB is designed for hardcore adventurers who want to take on bigger challenges...

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[speedkills]

Check out your other pedal as well. Not much to do wrong there that I can think of other than some can be a bit tricky to get in perfectly straight. I mean unless you massively overtorqued it and literally stripped it out, all I can think of right away is that you either cross threaded it when installing it, or somehow swapped your left and right pedals? Asking the simplest questions first, were you aware that one thread is normal, and one is reverse? When you installed them, did they thread in easily? If they don't go in all of the way with your fingers something is wrong, you should only need a wrench to do the final torquing down.

 

[urastus]

It could have been too loose, come looser on the ride and wear out the thread in the crank, which is soft. If you have a multi tool, it may have a hex bit large enough to get you out of trouble, next time.

 

[TheRealPoMo]

Happened to me recently. Only just managed to get it to bite on what's left of the thread in the crank ( which was loads more than you have left sorry to say). Loctited and backed away slowly. I'd replace the cranks immediately if there was not an apparent shortage of 165mm Bosch ones.