bottom bracket size

cerenko

Senior Member
Location
doncaster
can anyone advise me on how to find out what size bottom bracket I need to buy.
I am fitting a shimano 105 double chainset, not hollowtech to a Scott cr1 frame, will it be English or italian thread ?,The local bike shop no use at all, told me i need to buy two differant ones and try them.

Thanks pete.
 
Take the old one out, the size should be stamped on it, and it should be English I'd have thought :thumbsup:
 
unfortunately there is no bracket in there to take out.

Thanks anyway for the advise.

D'oh! If you can confirm the threads are English then the shell will be 68mm, but as for length that's anyone's guess, (assuming it a square taper BB), probably 120 - 125 mm ish.

Have you contacted Scott to ask them? Have a look HERE, they have online bike manuals going back to 2003, failing that send them an email is about all I can suggest.

Good luck :thumbsup:
 

RecordAceFromNew

Swinging Member
Location
West London
can anyone advise me on how to find out what size bottom bracket I need to buy.
I am fitting a shimano 105 double chainset, not hollowtech to a Scott cr1 frame, will it be English or italian thread ?,The local bike shop no use at all, told me i need to buy two differant ones and try them.

Thanks pete.

That is funny! I wonder which two do they have in mind...

It will be English thread. It is likely to be for 68mm shell width (and which you can confirm/measure frame with a ruler). The outstanding questions are which spindle type (square tapered or Octalink V1 if not Hollowtech - note some Hollowtech cranks use square tapered bb e.g. - to ensure the public is confused!!!) and length you need, which is dependent on the precise model code* of the chainset and the chainline desired (43.5mm road double and 45mm road triple for Shimano, but it does depend on whether you have a typical road double front mech which is designed to work with a road chainline).

* Shimano have been making "105" chainsets for donkey years with many incarnations to date, so the full model code (often stamped on a crank arm's inside surface) is usually necessary for certainty. This MIGHT be enough to inform. If not you can come back with more info.
 
OP
OP
cerenko

cerenko

Senior Member
Location
doncaster
Thanks for the help, Think i will take it to evans and let them fit it, if i take the chainset along they canot go wrong, can they ?
 
Top Bottom