Cottered Cranks...

[revo87]

Hey guys...

I'm having a bit of trouble fixing my bikes cranks... They're cottered cranks so I guess a little bit of trouble comes with the territory but come on...

Here's the deal... I didn't check the cranks out before I took them out and worked on them, but what I could see was that the cotter on the left was protuding like 0.5 cm... After fixing them up, bought new cotters and placed them back but I can't seem to find the balance between getting them to stay 180º from eachother and getting them tight... It's one thing or the other... bought a new set of cotters and tried that but it's still the same...

My only fear is that the hole for the cotter was widened from bashing it with a hammer / bad use or whatnot and there's nothing else I can do but to toss 'em...

Any ideas?

Thx =)

 

[Korporal]

Cotter pins come in three sizes. Did you get a smaller one?

 

[Bendix]

are the cotters in the right way? if you're looking at the cranks in the horizontal position the nut should be up on one side and the blunt cotter side up on the other. if both cotters are in the same direction the arms will be off by several degrees no matter how hard you hit things......

 

[revo87]

are the cotters in the right way? if you're looking at the cranks in the horizontal position the nut should be up on one side and the blunt cotter side up on the other. if both cotters are in the same direction the arms will be off by several degrees no matter how hard you hit things......

Yeah, they're facing opposite directions =) Truth be told, they weren't the first time i put them in :mrgreen: They aren't off by a whole lot, I'm guessing less than 5º, but it's hard to ride it like this

Cotter pins come in three sizes. Did you get a smaller one?

Hmm... Problem is I think I have to he a bigger one for the left crank than I use for the right one, otherwise it won't fit :? Do you think I can get different sized cotters with the same angle?

 

[deorman]

Either one of them is messed up, or you have a mixed set. You could get them to match by filing or grinding, or you can probably (I would) swap in a modern set.

 

[Korporal]

I agree with deorman. You have a mismatched set. I say grab a new axle, and some square taper crank arms. They'll save on the hammering next time you have to repack the bottom bracket.

If you really want to re-use the current set you're in for a bunch of tweaking.

 

[Bendix]

well, i've never had it happen in 25 years but we had the same exact thing happen at the shop yesterday! bone stock 70's nishiki. i wonder if the new chinese made cotters from j&b are a goofy taper..... of course it's all we can order, i suppose a guy could find some nos japanese made cotters on ebay......might be worth a try.

 

[Korporal]

Bendix, I got some cotters from a shop in Colorado Springs that didn't give me any problems. I could PM you their info if you want to see where they're getting their pins.