kroozer 

I just bought my first cottered crank, a Nicklin N34, which is identical to the Williams C34 and was produced from the 20's through the 70's(!!). It's pretty cool-- solid, shiny chrome steel. I am wondering what sort of BB options are available. How interchangeable are cottered bottom brackets? I'm talking about the crankarm-to-axle connection, where the cotter pins go. I could pick up a new one down at my LBS, but I have no idea if it would work. Thanks.

sailorbenjamin

Well, what kind of bike are you putting it on? Is it standard British/Japanese, Italian or French? That'll determine the length. I'm thinking the Williams were British which would have a 9/16" hole. The French and Japanese bikes have a 15mm hole. Almost the same but not quite. The depth of the cotter pin lands might vary some but you can compensate by filing (or not filing) down the cotter pins.
Edit: I meant to say 5/8" and 16mm

zukahn1 

Well for your BB options you get loose ball and cone, or raced and cone. If the cups are in fairly good shape not scored or pitted badly I would just put new bearings in and go with what you have you know it fits. Just get a set of new cotter pins Likely English size and rebuild it. Dont' fear older cottered tech with a little TLC it is perfectly fine on a older bike.

nlerner

Well, mostly you need to find an English cottered spindle. Here are the relevant dimensions from Sutherlands:

kroozer 

The crank is English and will go on an English frame (a 1940's Stallard) so everything will be English sized.
I don't have a BB yet.
As for axle length, it will be for a single chainring.
With regards to crank-axle fit, is the spindle end diameter the only variable here ?
Are the cups for cottered BB's any different from cotterless BB cups?

zukahn1 

The cups are basically the same if you can find some that fit into the frame you should be OK. If the bike is a English bike made before the mid 50's it will take the older type English thread often refered to as Raliegh or Phillips thread. Which are not the same as the modern English thread.

JohnDThompson 

No. Although it may take some experimenting to find an appropriate spindle for the crank of your choice.

JohnDThompson 

The Raleigh 1-3/8" x 26tpi standard was used well into the 1970s.

clubman 

Try to not mix any Raleigh in your BSC drivetrain. Axle widths can be minutely different and be too tight for Nicklin or Williams cranks. Cup centres can get tight too.

kroozer 

So any late 40's/early 50's English frame would most likely use Raleigh/Phillip's BB cup threading rather than BSC? Keep in mind that mine is a lightweight chrome-moly club racer, not a roadster. Unfortunately I don't have it here with me to verify the threading.

rhm

If so, that's a quite a surprise to me. I've overhauled a lot of English bikes of that vintage, mixing and matching cups and spindles etc to get the best fit, and though I can't say I've ever actually measured the threads, it seems to me standard BSC cups fit all the non-Raleighs. I know my 1954 Drysdale (American made frame, but all frame components are English made) came to me with a Campagnolo fixed cup and a Tange adjustable cup, both "standard English thread." I replaced them with period correct Bayliss Wiley which fit perfectly.

I'd suggest you try fitting standard English cups, gently, to see how far they thread in. If the frame threads are 26 tpi, the 24 tpi cups will go in easy for about 1/4" but then encounter more and more resistance. You'll know there's a problem long before you do any damage.

I don't think you'll have any trouble finding cups to fit your frame, but a spindle will be trickier. Cottered spindles made for cheap tenspeeds are longer because of the extra chain ring; spindles for old three speed bikes are longer to allow for the chain guard (the cranks have more space between the chain guard and the crank arm); and spindles for roadsters are even longer to allow for the full chain case. For a lightweight you want something around 122 mm.

Good luck! And don't forget to share some photos, please!