How To Remove A Cottered Crank Arm The Right Way: No Hammer Or Drill!

Please don’t use a hammer on crank cotters!
The cottered crank Installation video Is here: • How To Install A Cotte...
This video shows you how to remove old school, cottered crank arms in just a few minutes, without destroying the cotter or the crank bearings. Some are trickier than others (and sometimes you won’t be able to reuse the cotters), but this method works every time.
Hands down, the best cotter press I have used is the Bikesmith Design cotter press. The tool steel anvil is compact and rigid AF. The press bolt is concave to self-center on the cotter. Just a simple and well thought out tool, for reasonable cost. Bikesmith also sells the best replacement cotters available. I do not receive any commission or sponsorship from Bikesmith, it’s just the right tool for the job for shops or DIYers.
Link to: bikesmithdesign.com/
Link to: Cottered Crank Assembly video (coming soon)
Shop notes: When I had the full time shop, I would see these a 2-3 times a year. You would be surprised how many people are still rocking bike-boom Peugeots, Raleighs, Panasonics, and other pre-square taper bikes, and want their old cup and cone BB’s serviced.
I would also see the aftermath of people trying to remove these with a hammer (and occasionally a saw, 😬). Don’t be that guy!
About this bike: This is the early 70's Liberia road bike that I found at the dump a few weeks ago. The frame is bent, so I am stripping it for parts. I figured it was a good opportunity to show the best way to remove a cottered crank. Check out the Dump Find video on the bike here: • Dump Find! Vintage Roa...

[@SugoDiGatto]

Pushing rather than hammering makes me more comfortable to attempt greasing the bearings, I see no other option for me and that vintage folding bike I got... I'll see if I'll remember to report back with the results, I have quite a selection of C-clamps!

[@ReferenceBicycle]

Yes, the C-clamp method works fine. It’s just more cumbersome than using the BikesmithDesign tool. Good luck! 🍀

[@SugoDiGatto]

@@ReferenceBicycle I just tried with a massive clamp I have; no budging, the clamp started bending, it would have snapped a dedicated tool in half.
The pin doesn't even look that rusted, but no amount of clamping, torch heating, and pounding achieved anything!
I'll just leave it be and throw away the whole bike when the bearings will fail :(

[@BobaPat]

But how do we get the crank arm off it it's stuck? Got the pins out but the arm is stuck on

[@ReferenceBicycle]

I can honestly say I have never seen that happen before. I would try a 3-jaw gear puller. You can get them at Harbor Freight or Amazon. The spindle to arm bore is typically a slip fit, so I’m surprised it won’t release, unless it’s extremely corroded or somehow got deformed. No guarantees, but I would give it a long soak with Sea Foam Deep Creep then try a gear puller. Let me know how it goes.

[@EriebyCycle]

Interesting. I’m willing to wager that a c clamp for this job would result in a lot of swearing.

[@ReferenceBicycle]

Yeah, it’s not ideal. I haven’t done that method in probably 20 years, but it doesn’t stay centered on the cotter. You really need two sets of hands (3 if you are trying to use a bench vise). The Park and Bikesmith tools self center and make it a one-person job.