WTD: BB + Help!

[Fishheads]

Hi,
Looking for a bit of help with changing a old BB.
I have a road bike from the late 80s and I want to change the BB because it’s just generally old and heavy.

I'm not massively knowledgeable about bikes but I've learnt to do everything and change every on my bike as I've gone along but changing the BB really stumped me.

I thought it would be a straight forward job but I can't find any sizes on the BB at all, I'm not totally comfortable about measuring with a tape measure and getting exactly the right measurements etc.

It’s got square tapered ends with one being slightly bigger than the other, here is a picture with the measurements on it

I'm thinking maybe I should keep the spindle and get different cups just to save the hassle??

BTW I'm pretty sure the threads are English and the shell? is 68mm.

Cheers

 

[KermitGKona88]

Why not save all the hassle and buy a sealed b/b from chain reaction cycles RPM Sealed 68-118 or 68-122.5 £6

 

[kula]

I'd look at somewhere like chainreaction cycles and search for UN54.
Its a sealed unit so less hassle
There is a 68-118 or 68-112, which means 68 shell width and 118 spindle length.
Take your pick as depends on how accurate your tape measure is. You will also need a shimano BB tool that suits this type of BB as well, they (or copies of the Shimano ones0 are fairly cheap

 

[Fishheads]

I wasn't sure if I could buy one close to the size and kinda hope for the best.

I saw a "Tange Sealed Bottom Bracket Square Tapered 68 x 122.5mm" and didn't know if it would be fine or not.

 

[KermitGKona88]

What chainset are you running and how much clearance did it have on the frame before you removed it ?

 

[Old Ned]

To check the axle width I 'clamp' the axle in the top of a drawer and measure between the back of the drawer front and the cabinet. I have some old kitchen cabinets in the workshop. If you have a large vice the same can be done.