What bottom bracket

[biggs682]

hi i have a nice frame sitting doing nothing as it has no bottom bracket fitted , how do i owrk out what size to use ?? cant remember what make , will add when remembered .

 

[AlanW]

hi i have a nice frame sitting doing nothing as it has no bottom bracket fitted , how do i owrk out what size to use ?? cant remember what make , will add when remembered .

What make frame is it?

I seem to recall that unless its an Italian frame, the threads will be English.

Then just measure the width of the shell, to give you the width.

I would recommend fitting a Hope stainless steel BB or even the ceramic version. Just buy the road version and it comes with shims, so at least it covers your options.

Yes, it may be more than you would like to spend, but they knock the OE fit ones into a cocked hat. They are so smooth and also come in nice colours to.

 

[4F]

You need also to consider what cranks you are fitting as the BB will need to be compatable as well as the right axle length depending on whether it is single, double or triple.

 

[GrasB]

Assuming it's not a really old frame then the difference between British or Italian thread is easy, just work out if the threads are both clockwise (Italian) or if one is clockwise & the other anti-clock wise (British) the spindle length (107mm, 113mm, etc.) will come down to which cranks you want to use.

If it's seriously old then you need to break out the measuring tools & consult Sheldon Brown's BB page for measurements.

 

[Steve Austin]

Also depends what crankset you want to fit. Square taper? Shimano, campag? splined cranks? octalink/isis. or External BB? even they have two standards.

It will either be English or Italian threaded, and probably 68mm wide.

So you need to tell us a bit more

 

[AlanW]

You need also to consider what cranks you are fitting as the BB will need to be compatable as well as the right axle length depending on whether it is single, double or triple.

Excellent points and ones that I clean forgot all about!

And as all my bike now have external bearing, I forgot than any others exist.