# questions on bottom bracket and crank



## brewerkz (Mar 29, 2020)

new to early bicycles, looking for bottom bracket, crank recommendations for this bike, both switching back to cottered design or staying with square drive. 

The frame came with a Higgins badge. The bottom bracket width is 2.5".


----------



## juvela (Mar 29, 2020)

-----

the cycle's headset appears to be from Brampton

the original chainset may have been from the same maker, alternately something like Williams

have you been able to learn date or model for the bicycle?


-----


----------



## brewerkz (Mar 29, 2020)

possibly Higgins Ultralite - the label on the down tube was added after a bad silver spray paint.


----------



## bulldog1935 (Mar 29, 2020)

any chance you can pull the crank arms and let us see the bottom bracket better?
Not knowing what you have there, it may be necessary to determine if the shell threads have been altered.
The offset on the left side looks unhappy to me - there's never any reason to have left side offset.



A few new cartridge bottom brackets can match 26 tpi Brit thread cups.
There are also threadless bottom brackets that fit anywhere.
Any new BB would be a square taper.

A *Peter Underwood article on the marque* is always a good way to begin. 
Then follow up on this page for example bikes


----------



## brewerkz (Mar 29, 2020)

bulldog1935 said:


> any chance you can pull the crank arms and let us see the bottom bracket better?
> Not knowing what you have there, it may be necessary to determine if the shell threads have been altered.
> The offset on the left side looks unhappy to me - there's never any reason to have left side offset.
> View attachment 1163930
> ...


----------



## bulldog1935 (Mar 29, 2020)

so what BB came out of that shell?

Otherwise, have you tried chasing 26 tpi Brit BB cups on those threads?
There's always a chance somebody tried jamming 24 tpi ISO cups in there and we can't tell from photos.

If anybody in the US has a NOS bottom bracket that would fit the original threads, it would be Yellow Jersey.  I would call them and tell them what you have.


----------



## brewerkz (Mar 29, 2020)

bulldog1935 said:


> so what BB came out of that shell?



a shimano OCTALINK *BB-M952, 1.37x24.

photo appears like a sleeve  - would this have been added*


----------



## bulldog1935 (Mar 29, 2020)

That's a BSC bottom bracket.
Did the threads chase properly?
And yes, if the original threads were machined out and replaced with a sleeve, guess it could now be 24 tpi.


----------



## brewerkz (Mar 29, 2020)

bulldog1935 said:


> That's an ISO bottom bracket.
> Did the threads chase properly?
> 
> If anybody in the US has a NOS bottom bracket that would fit the original 26 tpi threads, it would be Yellow Jersey. Might call them and tell them what you have.



yes, agree totally wrong BB installed. Could a threaded sleeve have been added since the threads dont run to the edge of the bracket. The threads did chase properly.


----------



## bulldog1935 (Mar 29, 2020)

that's it exactly if the threads chased properly.
Your options are now any BSC BB.

I still don't like the way that left side offset looked, but it could be a factor of a too-wide symmetric axle BB, taken up with a spacer to get correct chainline.
Can you get the width of you BB shell in MM?


----------



## brewerkz (Mar 29, 2020)

brewerkz said:


> yes, agree totally wrong BB installed. Could a threaded sleeve have been added since the threads dont run to the edge of the bracket. The threads did chase properly.



appreciate your help !


----------



## brewerkz (Mar 29, 2020)

bulldog1935 said:


> that's it exactly if the threads chased properly.
> Your options are now any ISO BB.
> 
> I still don't like the way that left side offset looked, but it could be a factor of a too-wide symmetric axle BB, taken up with a spacer to get correct chainline.
> Can you get the width of you BB shell in MM?



agree, this is how it was acquired. I am thinking thru making it work with a square drive set up. But, is removing the insert and going to a threadless bottom bracket also an option?


----------



## bulldog1935 (Mar 29, 2020)

If you want the best cartridge, SKF from Rene Herse - definitely worth a call - I'm running these on 3 bikes.  (Phil Wood on my 26 tpi)





						Bottom Brackets – Rene Herse Cycles
					






					www.renehersecycles.com
				




ALSO NOTE - BSC are the threads you want, Rene Herse calls ISO the Italian threads, which are R/R, while BSC are R/L (reversed threads on left side)








brewerkz said:


> agree, this is how it was acquired. I am thinking thru making it work with a square drive set up. But, is removing the insert and going to a threadless bottom bracket also an option?



*Velo Orange sells the threadless BB*, and they go right in over the old threads, including the sleeve.

The threadless lets you dial in offset to get correct chainline, just how you tighten them in place.
With SKF, you get offset installing drive-side spacer.
Again, getting the correct axle width based on your BB shell width is the place to begin.


----------



## brewerkz (Mar 29, 2020)

bulldog1935 said:


> If you want the best cartridge, SKF from Rene Herse - definitely worth a call - I'm running these on 3 bikes.  (Phil Wood on my 26 tpi)
> 
> 
> 
> ...



I am coming up with a 45 MM chainline measuring with the rear wheel, with a narrow bb shell on the frame. I would either shim the BB to center it, or use the BB you suggested that allows positioning.


----------



## 1951 C.W.S (Mar 29, 2020)

That looks like a tricky bugger!
Hope you can get it open and clean!


----------



## bulldog1935 (Mar 30, 2020)

no offense, someone has already removed the fixed cup of the original BB, and replaced it with a modern cartridge BB.  
That results in the bike being easy to work on at home, but the shell thread sleeve makes it impossible to return to original.  

Here's an original 26 tpi BB shell, in which I used the Phil cartridge BB I show above with 26 tpi (original thread) cups.


----------



## brewerkz (Mar 30, 2020)

bulldog1935 said:


> no offense, someone has already removed the fixed cup of the original BB, and replaced it with a modern cartridge BB.
> That results in the bike being easy to work on at home, but the shell thread sleeve makes it impossible to return to original.
> 
> Here's an original 26 tpi BB shell, in which I used the Phil cartridge BB I show above with 26 tpi (original thread) cups.
> View attachment 1164515



thank you very much for your patience, I have a path now to making the bike a rider.


----------



## brewerkz (Mar 30, 2020)

bulldog1935 said:


> no offense, someone has already removed the fixed cup of the original BB, and replaced it with a modern cartridge BB.
> That results in the bike being easy to work on at home, but the shell thread sleeve makes it impossible to return to original.
> 
> Here's an original 26 tpi BB shell, in which I used the Phil cartridge BB I show above with 26 tpi (original thread) cups.
> View attachment 1164515



I was looking at cottered bottom brackets for fun....






						136mm Cottered sealed bottom bracket
					

The only sealed cottered bottom bracket avalible, uses shimano style splined cups 68mm shell, British thread (1.37' x 24tpi) 136mm measured from end to end of the axle. Centre to centre of the flats measures at 116mm




					www.sjscycles.co.uk
				




If I centered this bb with spacers - how do I calculate chainline of at cottered crank, they provide the flat distance, but how much does the chain ring sit inside the center of the crank?


----------



## bulldog1935 (Mar 30, 2020)

I didn't know you could buy that BB - SJS is a very good vendor.



			All About Bicycle Chainline


----------

