Cottered Crank.....

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Reading that cottered cranks can be hard to get off. Was going to lube bottom bracket on my '70 Raleigh Sports.
Only because I don't know when or if ever the previous owner or owners ever did.
It pedals smoothly and no noise. Should I leave or attempt it?
Thanks.
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One side off is all you need to grease it but it's better if you can get both off. I once had to drill the center of them out on an old Hercules as they were stuck so bad that I couldn't get them off. I guess in desperation you could take your seat off and dump heavy oil in there to douse the BB and then drain it out. I have one of these. No LBS have this tool. The hard part is getting replacement cotters as they are of poor quality and not specific enough for and exact replacement with out filing the flats. Keep and reuse your cotters if possible.
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I have used DuPont Teflon White Lithium Grease in the spray can to get in tight spots. Got to shake it up real good goes in like oil then sets up inside bearings.
 
I agree with horsefarmer. I would get one of those cans of the white lithium with the straw spray and spray a bunch in the gap between the cup and spindle to get it to the bearings. Then the cotters stay good. After a little riding, the bearings might need a little adjustment.


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Put the bike in a vice grip. Put a spanner socket over the non threaded and and clamp it into the vice. Screw the nut on the non threaded end so it is 3 threads on the pin. Put the nut on the other side of the clamp. SQUEEZE! You can do this with a hand held vice or if you have one screwed on your bench, take the wheels off and lift the frame onto it. Bikemanforu has a video on it.
 
I guess I tried to fix bikes with cotter cranks a couple of times and it was always unsuccessful. So I don't mess with them. Actually if it is smooth and quiet I would leave it alone. :thumbsup:
 
Cottered cranks were the standard 80 years or so, proof that they do work well. You do need to file the cotters to fit, make sure you have the right size/diameter cotters and use a press to install them- just tightening the nut does not draw them in as tightly as they should be. A press also makes removing old cotters painless. Bikesmith Design has a good compact press which works better than most home made contraptions:
http://www.bikesmithdesign.com/CotterPress/
 
Here's what Al Carrell says in "The Super Handyman's Big Bike Book."
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Sometimes a hammer won't do it. I think the wooden block with damp the blow of the hammer. I've hit Cotter pins with a bare metal hammer and they've still not come out. The method were used the large bench vise is the best. And even that it takes a lot of strength to get the Cotter pin out. I remember I was removing one out from an old Raleigh record and it took a lot of strength to get the Cotter pin out but when the it broke a loose on the bench vise it almost set my face flying into the bike. If once you push the Cotter pin out but it doesn't go all the way out and it's flush with the crank then you can use a punch with a hammer.
 
Most people use a bench vice with a wrench socket over the non threaded end of the cotter for the cotter to drop into. Often this doesn't work on something like a 1950s bike that has been out in the elements. Drilling the cotter hollow has worked for me in these situations. Sheldon Brown even broke a large bolt cutter type of cotter removing press trying to extract a stuck cotter. I use grease when putting in cotters.
 
Most people use a bench vice with a wrench socket over the non threaded end of the cotter for the cotter to drop into. Often this doesn't work on something like a 1950s bike that has been out in the elements. Drilling the cotter hollow has worked for me in these situations. Sheldon Brown even broke a large bolt cutter type of cotter removing press trying to extract a stuck cotter. I use grease when putting in cotters.
Most people use a bench vice with a wrench socket over the non threaded end of the cotter for the cotter to drop into. Often this doesn't work on something like a 1950s bike that has been out in the elements. Drilling the cotter hollow has worked for me in these situations. Sheldon Brown even broke a large bolt cutter type of cotter removing press trying to extract a stuck cotter. I use grease when putting in cotters.
If you have a bigger bench vice, which I use, the cotter will force out. I use a vintage, cast iron bench vice with a 1 foot long steel handle. The other bench vice is another vintage, cast iron one but the other one is the size of a grapefruit. I don't think it could do it. The big one is the size of a human head.
 
If you have a bigger bench vice, which I use, the cotter will force out. I use a vintage, cast iron bench vice with a 1 foot long steel handle. The other bench vice is another vintage, cast iron one but the other one is the size of a grapefruit. I don't think it could do it. The big one is the size of a human head.

I have 5 bench vices ranging from tiny to huge and everything in between. Even the huge vice would not remove one of the crank pins on my 1950s Camelback Hercules. One came out hard and the other one ended out with a mashed bolt end (I used the nut to put the pressure on). After drilling out the center it came out. This crank had three problems, it was rusty from being in the elements, no grease was applied when it was rebuilt a generation ago and the pins were installed wrong so that the crank arms were not 180 degrees opposed. What a mess. Otherwise one of my two crank pin tools usually does the job. I think the installer really pounded the pins in thinking that if he put them in tight enough the crank arms would end out at 180 degrees. Then in disgust he tossed it out in the yard and there it remained for years. The head tube was also badly banged up and dented from efforts to remove the frozen in cups. Apparently he didn't know that these are removed from inside. Weld filling, JB Weld and filing fixed this. It's now a nice bike.
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