Crank Cotters
$3.50-$4.50 each

S&H $9 (in the USA)

No additional S&H charge for Cotters when mailed
with Cotter Press and/or Fixed Cup tool.

Click here for ordering, payment and shipping info
MN residents add 6.875% sales tax
(7.775% if you are in the metro area)

When emailing me about cotters, please include the word "Cotter" in your subject line.

The quality of cotters available to most bike shops from the major suppliers is pretty sad. (See Grade D below) So, I am always on the lookout for any high quality ones that might still be out there.

Grade A cotters are fully machined from 3/8" (9.5mm) or 9.0mm steel. Even the nuts are turned on a lathe. Both ends are domed to prevent mushrooming when they are installed or removed. The threaded stems are larger, 7mm and the washers are thicker and harder.

When you compare the moments of inertia for the actual root diameters of rolled 6mm and 7mm threads, you see that the larger threads have twice the resistance to bending.  This is irrelevant in use, but potentially a big deal when trying to remove one that is really stuck.

9.5mm English Grade A
Modified (Raleigh) cut $4.50 each - Cut is 27mm long and 2 mm deep - 7mm stem
Original cut $3.00 each - Cut is 18-20 mm long and 1.35-1.45 mm deep - 7mm stem
I do not have any cotters that will accept Raleigh "R" nuts.

The 9.5mm Grade A cotters are not cut deeply enough to be a good fit for Raleighs.   For non-Raleigh owners, this is a good thing.  Cotters cut to fit Raleighs go in too far for other cranks.  Filing cotters to fit whatever cranks you are working on used to be the norm.

These days, not everyone is comfortable trying to file a pair of cotters to the correct depth and and at the same angle.  So, I made a fixture that allows me to accurately machine them to be a good fit for the typical Raleigh crank.  Unfortunately modifying the cotters eats up time, so I have to charge $4.50 each for the modified ones vs. $3.00 for the unmodified cotters.

9.0mm "French" Cotters are  $3.50 each

9.0mm Cotter Details
(Dimensions approximate due to manufacturing tolerances.)

1/2 Cut varies in length between 13mm and 16mm - 7mm stem (Limited supply, shopworn, may not be a cosmetic match)

3/4 Cut is 20mm+/- long - 7mm stem These are recent production "Grade A" from the same manufacturer as our 9.5mm cotters.

Full Cut: Out of stock, probably permanently.  Buy 3/4 cut and file them to fit.

Peugeot Cut : Cut runs full length of the cotter and is about 3mm wide at the end. 
Peugeot cotters are out of stock, probably permanently.
I have a few 9.0 cotters with a 6mm stem that you might try filing to fit. Cut is too deep for a 7mm stem.

  Not all Peugeots take the “Peugeot Cut” cotters.  Some with Nervar cranks take a cut and they may require some filing to fit.  Do the flats on your current cotters extend all the way to the end, like the “Peugeot Cut” cotter shown above?

For 8.0mm and 8.5mm cotters and 9.5mm Grade B Cotters try Bike Tools Etc.
Get their "Machined" cotters. Their "Stamped" cotters are like the Grade Ds shown below.

Grade D
These are what the major importers are bringing in today. The newest cotters are just pinched off a piece of rod, rolled and mashed into a usable shape. Since the bevel is just stomped into place, there is a bulge at the sides. So, they have to use undersized, 9.2mm or 8.7mm rod so the bulge won't keep them from fitting into a 9.5mm or 9.0mm hole.

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