Cottered Cranks

Replies to This Discussion

Permalink Reply by Alan Matejka on November 11, 2009 at 7:33am

I have found that replacing pins in matching pairs works well. Back in 1972, In Japan, One of my crank arms came loose. I found a bicycle shop. The man at the shop installed my pins with a brass hammer. He then tightened the nuts. In 1972 I was in the U.S. Army. I purchased pins at the shop on Ashland, just south of North Ave. Also at Beverly bike shop, at 91st and Western. Good luck with your cranks. Alan.

Permalink Reply by Alan Matejka on November 11, 2009 at 7:48am

Also check Sheldon Browns article on cottered cranks.

Permalink Reply by globalguy on November 12, 2009 at 7:59am

Ah, the perennial cotter pin issue! I ran into the same problem when I started my Raleigh addiction. For a long while my cranks were always off by 5-15 degrees. Then I saw the following in an old Raleigh owner's manual: The pins were facing in opposite directions!

What I mean is that when you have the two cranks in the horizontal position, the left side pin should enter from the top and bolt underneath and the right side pin should enter from the bottom and bolt on top - or visa versa. I'm not quite sure why happens but it works for me! Perhaps Allan knows why?

Permalink Reply by Alan Lloyd on November 12, 2009 at 9:32am

If you don't have the cotter-pins facing "the opposite way", as Garth says, the cranks will be significantly far away from 180 degrees.

Just a few degrees off probably means the cotter-pins aren't a matching pair or, perhaps, one has gotten deformed. It is also possible that the cranks aren't a matching pair, if the problem persists with new & matching cotter-pins.

Which direction the cotter-pins should be inserted is one of those ongoing arguments and I can't even remember which way I tend to use without looking at them. Sometimes the cranks themselves "tell" you, as a cotter-pin goes in easier one way around.

It is always best to push the cotter-pins with a press, rather than clout them with a hammer - which can damage the bearings in the bottom-bracket - but if you have to hit them, support t'other side with something!

Most bike shops still stock cotter-pins, I think you want the 9.5mm size (the fat ones) for a Raleigh?

PS: Garth, I'm also an "Alan" with one L ...

Permalink Reply by Barry on November 12, 2009 at 10:41am

Hello fellow pin-heads (har)

There's a fellow in Minnesota that makes a useful pin press:

His site is bikesmithdesign.com. He also sells cotter pins and other items for keeping old 3-speeds in top form. Here is his pin press page.

I haven't searched chainlink but his name has probably come up before.

Permalink Reply by Alan Lloyd on November 12, 2009 at 10:50am

He's Mark Stonich and I have one, they're excellent - check out his web-site http://www.bikesmithdesign.com ...

Barry said:

Hello fellow pin-heads (har)

There's a fellow in Minnesota that makes a useful pin press:

His site is bikesmithdesign.com. He also sells cotter pins and other items for keeping old 3-speeds in top form. Here is his pin press page.

I haven't searched chainlink but his name has probably come up before.

Permalink Reply by Barry on November 12, 2009 at 10:57am

Alan good to hear!

Did you also buy his fixed cup tool?

Mark sold me a custom modified part for an old five-speed hub. The guy is a mechanical genius. I love that he shares his knowledge so freely.

Permalink Reply by Alan Lloyd on November 12, 2009 at 11:25am

Yes, and it works really well too!

I've met Mark several times, as has Garth, when we've been on the Lake Pepin 3-speed tour and went up to the ABCE event in Minneapolis.

Barry said:

Alan good to hear!

Did you also buy his fixed cup tool?

Mark sold me a custom modified part for an old five-speed hub. The guy is a mechanical genius. I love that he shares his knowledge so freely.

Permalink Reply by globalguy on November 12, 2009 at 10:24pm

HOLY CRAP!!! We now have contact between The Windy City and the Twins ... as far as 3speedsters go ... thanks A(l)an!

Alan Lloyd said:

Yes, and it works really well too!

I've met Mark several times, as has Garth, when we've been on the Lake Pepin 3-speed tour and went up to the ABCE event in Minneapolis.

Barry said:

Alan good to hear!

Did you also buy his fixed cup tool?

Mark sold me a custom modified part for an old five-speed hub. The guy is a mechanical genius. I love that he shares his knowledge so freely.