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Old 02-12-19, 02:25 PM
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Originally Posted by BigChief View Post
Just for future reference, I'll describe my plan B for this situation. So far, I've never had to go beyond this to be successful, but who knows? I may someday need a plan C but I haven't yet. If I see the threaded end of the cotter start to bend from pressure from the press, I file a small flat on top. Then I center punch the pin by eye. Then, starting with a small drill and working up in size as I go, I drill down into the threaded end of the cotter. The last drill I use is almost the size of the clearance hole around the cotter. I drill down until I'm well below the edge of the crank arm. Now, the drill leaves a nice countersink perfectly in line with the cotter. Then I find the biggest punch I have that fits neatly into the countersink. Then I lower the bike stand until the wheels are on the ground. Then I drill a hole in the end of a 2x4 big enough to clear the cotter. Then I fit the 2x4 so it fits snugly between the cement floor and the crank arm. Since the spindle and crank arm is being supported by the cement floor and the 2x4 and the force of the hammer blows is being directed exactly where it's needed, I have a lot more power on hand then I did with the press pushing against the threaded end.
My approach is far less sophisticated! I remove the threaded end of the bent cotter with a drift punch and hammer. I apply some penetrating fluid (my preference is a 50/50 mix of acetone and automatic transmission fluid) and wait at least 12 hours or so. Then I use a stainless steel socket that's got at least one end smaller than the crank arm opening for the cotter, and position the BikeSmith driver over that socket and then crank it down. That has usually done the job. I've had to drill out a couple of broken cotters, and it's a pain unless you have fresh bits and a drill with lots of oomph. Well, even then it's a pain.

I've also tried the approach to just keep riding the bike in hopes that the cotter will eventually get loose. That's worked once or twice, but not with any regularity.
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