Square Taper Bottom Bracket Query

[atlantis]

Hi !
My bike Btwin fitness 1.
There was some play in my bottom bracket and I opened re greased and tightened it.
The brand is a Vp .
Thought I should install a shimano instead
Following is the specification with images:

My link

After checking the measurements with a scale and reading the sticker , i realized that the available shimano bb are of 68x 18, 68x122 and 68x 122.5.

Since i need a 68 x 120 , which size would be appropriate, I am unable to source the same size.
What does the BC 1.37x24T stand for.
Should there be any other specifications that I need for a bottom bracket sizing ?

 

[Moodyman]

I think 68 x 122 will be fine for you. It's only 2mm.

Bottom bracket width is only to ensure that your front chain rings are relatively in line with your cassette at the back. This helps give you a straighter chain line.

Ohh...and Shimano UN54 in pretty decent.

 

[lukesdad]

BC is english thread. 1.37 is thread diameter in inches 24 thread pitch in threads per inch. Hope that helps.

Dont get an italian one now will you ?

You really need to put these type of threads (excuse the pun) in know how

 

[albion]

Check you current chain line using the middle rings.You can then judge which will be better centred.

 

[atlantis]

Thanks for replying

I think 68 x 122 will be fine for you. It's only 2mm.

Bottom bracket width is only to ensure that your front chain rings are relatively in line with your cassette at the back. This helps give you a straighter chain line.

Ohh...and Shimano UN54 in pretty decent.

If I use the 68 x 122 the size would equally increase on both the sides by 1mm, right ?

 

[PpPete]

Thanks for replying


If I use the 68 x 122 the size would equally increase on both the sides by 1mm, right ?

Yes, the spindle will stick out by an extra 1mm on each side.