Bicycle Mechanics - Slightly Loose Cottered Crank Arm - Whats the easiest Remedy?

This old 70s or 80s Raliegh 3 speed I've recently bought has Cottered Cranks. After a 3-4 days of riding around town. the Left Crank has become a little loose.

You can just feel the play in the Crank as it swings over vertical. So what is the easiest / fastest Cheapest way to fix?


I"m in Central East London. should I just take it into a Cycle Shop? are they going to have the right equipment to fix?


Do I need to pull it out completely?
or can I just tighten it up with a wack of a hammer?

Try driving the cotter in with a hammer but be sure to support the crank at the spindle end to avoid damaging the bottom bracket bearings. Tighten the fixing nut firmly once the cotter is reseated but don't try to reseat the cotter by just tightening the nut.

Whats the easiest Remedy?


Upgrade to a modern crankset honestly! No, I had a Raleigh 3-speed for a long time that I constantly battled on keeping the cotter pins tight. After I thought I had them tight once, it turns out that I had "bashed" them in too hard and the cranks were actually not completely 180 degrees from each other.

I rode my cottered cranks with absolutely NO confidence. I feared standing to pedal and eventually garaged the bike largely because of those damned pieces of crap.

Best way is just to get rid of them!

Upgrade to a modern crankset honestly! Best way is just to get rid of them!
That may not be so easy if the bike has Raleigh's old style proprietary bb threading. If it's standard English threading I agree, upgrade to a new crank.

Upgrade to a modern crankset honestly! No, I had a Raleigh 3-speed for a long time that I constantly battled on keeping the cotter pins tight. After I thought I had them tight once, it turns out that I had "bashed" them in too hard and the cranks were actually not completely 180 degrees from each other.

I rode my cottered cranks with absolutely NO confidence. I feared standing to pedal and eventually garaged the bike largely because of those damned pieces of crap.

Best way is just to get rid of them!
Were the cotters faced in opposite directions? If they are oriented with the nuts both pointed the same way, it will result in the cranks not being exactly 180 degrees.

Dan - Nah, I had them opposite -- I just applied so much force in driving them in that they deformed against the bb axle and were probably 1-2 degrees from 180. I tried installing new pins with a much lighter driving force, and after 20 miles they would be slightly loose (but enough to drive me nuts).

HillRider - exactly the problem with a lot of 3-speeds. Either drown a ton of $ in Phil Wood threaded bb's or garage it (like I did).

Most likely, the pin needs to be replaced. If it's been ridden to any extent while loose, the pin will suffer damage:

http://www.os2.dhs.org/~john/worn-cotter.jpg

Remove the pin and inspect the angled face. If it has transverse grooves as pictured above, it needs to be replaced. Take the old pin in to your LBS to have them match it to a replacement; there are several diameters and angles available, but Raleighs in general will use a standard 9.5mm pin. Use a cotter press rather than a hammer to install the new pin if at all possible. And be sure to check the other side as well.