Bicycle Mechanics - fix yer crank with j-b weld

this is for all you broke people with a broken crank arm hole who ride $40 bikes from the salvation army.

you can use j-b weld epoxy (hardware store, auto store) to fix it for $5. i have ridden 100+ miles on mine over big hills and i am 220lbs.

maybe i will have trouble replacing the BB, but i dont care.

i had tried other 'cheap methods' .. drilling a hole in the axle was too difficult (hardened steel), shims didnt work, i had no welder and only one car battery for 'battery welding', locktite '1 minute' epoxy is too soft, and jb 'stick weld' is not strong enough.

i slathered the normal ordinary jb weld over the axle taper and inside the crank hole, then put the crank on, then put the nut on the axle thread, then kinda tightened it (thread was stripped , and broken), and then slathered jbweld all over that. i waited about a day and a half and rode off into the sunset.

keyword: pedal arm, crank arm, jb weld, j-b weld, epoxy, welding, stripped

this is for all you broke people with a broken crank arm hole who ride $40 bikes from the salvation army.

you can use j-b weld epoxy (hardware store, auto store) to fix it for $5. i have ridden 100+ miles on mine over big hills and i am 220lbs.

maybe i will have trouble replacing the BB, but i dont care.

i had tried other 'cheap methods' .. drilling a hole in the axle was too difficult (hardened steel), shims didnt work, i had no welder and only one car battery for 'battery welding', locktite '1 minute' epoxy is too soft, and jb 'stick weld' is not strong enough.

i slathered the normal ordinary jb weld over the axle taper and inside the crank hole, then put the crank on, then put the nut on the axle thread, then kinda tightened it (thread was stripped , and broken), and then slathered jbweld all over that. i waited about a day and a half and rode off into the sunset.

keyword: pedal arm, crank arm, jb weld, j-b weld, epoxy, welding, strippedSounds great! Make sure to save some of the JB Weld to fix your broken teeth or jaw after you crash!

Sheldon "Not THAT Cheap" Brown

I don't think JB Weld will work on a broken jaw Sheldon. Could be wrong. Usually am.

but how am i going to crash? the crank is not going to 'pop off', its going to slowly work its way loose like it did before.

the crank arm hole was rounded a little, so the crank arm had a little play. the nut stayed on the axle, the threads were so screwed up you couldnt get it off except by pedaling it. so you could ride it a few blocks before it came off. the only thing thats changed is now theres a bunch of epoxy filling all those little nooks and crannies.

m8 ..i have another method
try the classifieds and buy the parts you need to fix it properly or buy a 10$ bike or better yet 5$ bike from the "salvation army " as you stated above and repair it properly with the new "used" parts . so we wont see you end up hurt from a bad thing gone worse
Cheers T

Yup. I love JB Weld. Have used it for LOTS of stuff.

Have seen it fail, properly applied to surfaces it's SUPPOSED to work well with, more times than I'd care to admit.

Your cranks? Okay (I actually wouldn't recommend it for ANYBODY's cranks).

Not mine, please.

When yer crank breaks crankin' up that big hill you're going to land right on yer crank - and that's gonna hurt

If your crank is still bolted on, and this is just eliminating wobble, good work :beer:

Dude, you can get a crankset for like $5 if you wanted to. Or $20 for a NIB one. What's that word for being excessively frugal?

Think about what's going to be between most of your 220 lbs and that top tube when your crank fails.

The only two engineering principles most people need:

"If it's supposed to move and it doesn't, apply WD-40.

"If it moves and it's not supposed to, apply JB Weld."

Dude, you can get a crankset for like $5 if you wanted to. Or $20 for a NIB one. What's that word for being excessively frugal?


Are you implying that a new crank costs the same as a pack of JBweld? :D

Sheldon

I had a bad experience with JB Weld. My brother used it to connect the pedal on his unicycle to the crank arm after the threads stripped out. It held for a little while then started working loose again. Apparently all the alternating shear/compression/tension forces from the pedal don't play nice with the stuff.