Saturday, August 8, 2009

Be Here, Now

Sometimes I''m amazed at how absent-minded & stupid I can be when it comes to bike mechanics. I get in the garage and I'm thinking about work. Just really not all there.

My latest adventure was ruining a perfectly good crank set. I was replacing a chain ring on a Pake 130mm BCD crankset, and the new ring was just small enough that I couldn't work it behind the spider arms, so I had to remove the crank arm. Easy enough. It was a tapered crank, so I reached for my usual crank remover, but I couldn't find it. Then I noticed a spare one I had bought awhile ago, and pulled it off the board to use it. It threaded on OK. But then it bottomed out, and no matter how hard I levered it, it wouldn't start pulling the arm off the spindle.

This is where it gets really stupid.

Instead of backing it off and trying to figure out why, I reached for a cheater bar.

Stupid enough for you? Wait, there's more.

With the leverage of the cheater bar and the crank arm, I still couldn't get it to budge, so I reached for a second cheater bar to slip over the crank arm.

And sure enough, the additional leverage got the puller rotating again. And thus I managed to repurpose a perfectly good crank puller as an efficient thread-stripping device.

The puller I was using was for Octalink, not tapered cranks. The wide (22mm) pad bottomed out against the inside of the crank arm, not against the spindle, and any additional force went into pushing the threads out.

Well, if there's a bright side to this unremittingly grim story, it's that I got to use an automotive ball joint remover to remove the crank arm. Not pretty, but it worked. (See? Cars are good for something!)

Oh, and there's a rumor circulating that you can remove a stripped crank arm by pouring boiling water on it, causing the crank arm to expand just enough to be pushed off the spindle. Yeah, right.

Besides, I like bashing things.


Andrew said...

Sorry, Ted. I'm impressed, though, at the efforts you went through to remove those threads from the crank arm! Maybe it's an aesthetic improvement!

Ted Diamond said...

The inside of the crankarm was smooth as a baby's bottom.

Nic Pottier said...

Man, I hear you, for a while there it seemed every time I wanted to pull a crank I had to get a new crank puller. Square -> ISIS -> Shimano BS

I actually thought I was going to have to do it yet again when I was cleaning out my 3 piece crank a little while back until I actually looked it up and found they were self extracting if you did it right. At least they seem to have figured that out.

All that stuff seems a bit contrived though, solution looking for a problem. Yes, you could round out the square brackets over time if you didn't keep them tight, and I snapped my share of those free riding, but was it really worth the adoption, then abandonment of ISIS and octalink?

I wonder how long the now even more proprietary 3 piece systems will last before they come out with yet another.