stripped extraction threads in cranks... both cranks...

OK… so i go to remove my ooooooooold Shimano 600 cranks to upgrade today…

The extraction threads on both crank arms… YES BOTH CRANK ARMS… shat the bed and crumbled…
The anchoring part of the extraction tool just pulled them straight out as if the threads were made of chalk…

Now I know you are probably thinking ‘oh you stupid dick, you didn’t tighten the anchoring component of the extraction tool before extraction’… but i did.
I have easily removed over a hundred pairs of cranks and I have never ruined the threads on any… and then I ruin both crankarms on my own bike at once…
I’m sooooooooooooo pissed off and frustrated.

Anywayyyyyy…

I wacked the crank bolts back in and rode home… thinking tomorrow I will either try and make a makeshift expanding bolt system from big nuts and bolts from Bunnings, placing them between the inside of the LHS crankarm and the RHS spider below the BB shell, hoping to work at least one arm loose/off the spindle… so that I may rescue and re use the existing BB

OR

I fire up the angle grinder and cut that shit off… so i can reach the BB with the appropriate tools to remove… killing the cranks and BB.

If anyone has dealt with this before please give me some pointers before i result to the angle grinder…

It’s a sealed cartridge BB not cup and cone.

thanks a bunch…

FML

I’ve taken a destroyed crank off with a hacksaw, the crank is way softer than the bottom bracket and you will feel when you touch it and obviously the aluminium will clog the blade as it is pretty soft.

a rubber mallet and a good eye?

thanks guys, taking it all onboard…

Ride it. Just keep doing short laps around the block until they come loose. I’ve done it once before - it worked a treat. Shame I wasn’t trying to get them loose.

Get hold of a small car pulley extractor.

if you dont care for the parts - hacksaw.

there are other ways to do it, but you’ll be paying a lot to get them off.

+1 works well.

+2 I’ve done this more than once.

You can use a hammer and bash them off. Before you get stuck into it, give the crank a really solid hit from the top, which can help break the seal between the crank and the BB spindle.

+3. A squirt of penetrene or wd40 might help things along a little.

first of all, thanks for all the suggestions!

wow this was an ordeal…

First I tried banging it off with the hammer from the inside of the crankarm to no avail…

then i rigged up the vice inbetween the RHS spider and LHS crankarm and started to unwind the vice to force them away from each other… this cracked the threadlock on the vices actual moving threaded rod so it begun undoing itself… i leant vices are only meant to have load applied in the one direction (to grasp) haha.

i ended up getting the hacksaw and cutting down to the square taper axle which relieved the tight grip the crankarms had on the axle and i was able to hammer them off.

off with the shimano 600’s and on with the Ofmega Mistrals :slight_smile:

winning feels so good! hahaha

Cheers,
Sime

it’s all over now, but there are a few tools floating around which work on a similar principle to the standard crank puller. they use claws that go around the crank and then push down onto the spindle. i’ve never used them or seen them, but i’ve heard of them being used in situations like this where you want to preserve the cranks.

why didnt you ride around until they came loose?

Come to think of it i have several of these tools that you talk of.
I use them for removing stuck heads (handles) off of taps. the reach around the bottom of the head and then you wind a pin down. I have a couple expensive ones ($300 a pop) but i have found my favorite pair is the harron ones from bunnings. They would work perfectly for pulling cranks and from memory are only about 20-30 bucks

Can post a pic from google images… do they have a particular name?

Beats me. I’m a huge fan of simple and effective.

But it was worth a chuckle reading all the convoluted ways to get cranks off.

i didn’t just ride around till they fell off because i was at work and wanted them off then and there so I could ride around to my parents house, give Dad a big fathers day hug, drink some beer and eat a big fuck off plate of roast vegies and cous cous… the food so awesome they named it twice.

I have had this happen before, crank puller stripped the extraction threads. Then I nearly ruined an auto puller. Bent the spider backwards trying to whack it out with a sledge. Took to them with the grinder in the end.

The frame survived unscathed…

will tell this story because i know its dumb/funny… just tried to pull of cranks to swap frames and stripped out all thread… got the shits real bad… went back out after a sapporo and realized i had not pulled the crank bolt off first…mmmmm real stupid… lucky the cranks in question are nothing special.laugh now