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Old 05-12-11, 08:56 AM   #1
jshapiro
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Stuck (literally) on Peugeot fork and crankset

Hi! I've got an old Peugeot bike that I'm trying to refurbish and convert to a fixie. It's not in very good condition. I'm in the process of taking all the parts off so I can sand it down and repaint it. I can't get the crank or fork off, however.

The fork should be the easier problem to solve, but I can't seem to figure out how it comes off. I unscrewed everything that looks like it can be screwed but the fork still isn't budging from the stem, which makes me think there is still something holding it down.

I also can't tell if it's supposed to detach here at the unpainted metal:
http://imgur.com/a/OVmHn#ptSeR

or down here at the bottom of the fork:
http://imgur.com/a/OVmHn#Rk6LO
http://imgur.com/a/OVmHn#mRhec

They both look like it should come apart here but they're not even wiggling. No amount of wd-40 has helped either. Anybody know if I'm going about this the wrong way?

The other problem is the crank cotters, which are fairly screwed up.
Compounding the problem is the fact that I don't have any bicycle-specific tools or any good punches short of a screwdriver.
http://imgur.com/a/OVmHn#5xk4J
http://imgur.com/a/OVmHn#PorfV

Anybody have any tips or have an unusual method that worked for them? Judging by how much of a pain these are I'm almost definitely going to just buy a new crankset so I don't have to deal with them anymore (which defeats the purpose of my project bike a little though .) Therefore I won't mind too much if you have a method that will ruin the crankset (obviously not preferable though.)

Thanks for the help! I've been reading old posts from this site all week, you guys seem great!

Last edited by jshapiro; 05-12-11 at 08:59 AM. Reason: grammar/spelling
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Old 05-12-11, 11:56 AM   #2
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For the stem, rethread the bolt back in three turns and tap it with a rubber mallet. That should free the wedge and allow the stem out of the steerer tube. The fork does not come apart at the crown. You are looking at the crown race.
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Old 05-12-11, 01:09 PM   #3
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Thanks! Worked like a charm. Now I just need to get this damn crank off...
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Old 05-12-11, 01:15 PM   #4
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I've never seen cotters protrude that much. Have you been partially successful, or did they come on the bike like that?
Anyhow, no need to despair. Can you still identify which is the narrow end? If you can, get yourself a proper drift punch, maybe a decent hammer. Also, figure out a way to support the crank when you begin to whale away at the cotter. Required reading here:

Cottered cranks aren't that bad really. Filing new cotters takes a bit of skill/patience, removing old ones is often a question of carefully applied violence. But on the whole BBs don't requre service often enough for this to be a huge issue.
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Old 05-12-11, 02:32 PM   #5
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I've never seen cotters protrude that much. Have you been partially successful, or did they come on the bike like that?
That's how they were when I got to them. It's possible someone tried to work on them in the past.

I think I must be doing something wrong. I got out the spindle on one of the pedals and tried to use it as a punch. I've been hammering for a good 15 minutes and it hasn't budged. The top is mushroomed now and the punch is starting to bend a little.

I looked into the hole on one of the cotters and it looks like it's screwed in. So I tried to grip the cotter with some vice grips and see if it would give but still no dice, and now the end is even more messed up from the teeth on the grip.

This really sucks. I was hoping to be able to get all the paint off today but this is taking way longer than expected.
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Old 05-12-11, 02:56 PM   #6
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I'm beginning to think that someone did try to work on those before, and really bodged the job. I've never seen a cotter that was screwed in. They're basically wedges, with a threaded neck to hold them in place once properly seated. Have you read the Sheldon Brown article on how to prop the crank up before you start hammering?

Otherwise drill and heat is your next resort, all explained in the Sheldon link.

I fear that you are causing considerable collateral damage right now...
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Old 05-12-11, 03:03 PM   #7
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After a heroic effort with the hammer and a considerable amount of wd-40 I got one off. I'm guessing I've ruined the crank by now though but I was afraid I was going to have to replace it anyway. The BB might be alright though, but I guess I'll have to change out the spindle if I don't want to use a cotter crank?

Thanks for all the help guys... I'll let you know if I have more trouble with the other one (keep me in your prayers)

Edit:
Done! Out back with paint stripper on as we speak
I couldn't get the second cotter out but I managed to get the BB off and that's good enough for me.

Last edited by jshapiro; 05-12-11 at 04:05 PM.
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Old 05-12-11, 07:17 PM   #8
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i couldnt get my cotters out either. THe more you bang on it with a hammer the more screwed you are going to be. If you wreck the bottom bracket and the bearings by using a hammer good luck finding another french set. DO NOT Hammer on it. IF you dont know how to get it apart ....take to to someone who does before you ruin it. That is about the only advice i can give. Ive been through the same thing. I ended up using a cut off blade on a angle grinder and cut mine at the bb axle. Took 2 seconds and no damage. YOu will have to get another bottom bracket axle but that isnt a big deal.
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Old 05-13-11, 01:16 AM   #9
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After a heroic effort with the hammer and a considerable amount of wd-40 I got one off.
Congratulations!

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... I'm guessing I've ruined the crank by now...
I don't quite understand why you're worrying so about the crank. Where's the damage to that? Did you hit it with the hammer? It's solid steel, so apart from messing up the chrome it should be structurally OK.

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The BB might be alright though,
If you didn't support the crank, but whaled away with the bike standing on its wheels, then the BB may well be damaged. It's possible to put dimples in the cups & the bearing races that way.

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...I guess I'll have to change out the spindle.
See above.

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..I guess I'll have to change out the spindle if I don't want to use a cotter crank?
Yes.

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I couldn't get the second cotter out but I managed to get the BB off .
Which should make it easier to position the crank for efficient hammering or even drilling, to get that one too.
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