Originally Posted by
DaveM
Hi
Just taken BB off my road bike, on the inside it says - BB -UN71 and on the side it says BC 1.13 68, now then I've done a search for BB and I can't find a UN71 and when I look at other BB (UN54) I can't find on thats BC 1.13 68, can someone advice me on what to do
Thanks
"UN71" is the Shimano brand model number.
"68" is the width of your bottom bracket shell (68mm). The other common width is 73mm.
"1.13" is probably the length of the bottom bracket spindle. It's usually expressed in mm, so I'd be expecting it to read "113". However, you can always measure the length with a ruler to verify.
Basically, if you match the width (68) and length (113), and crank arm interface (like square taper), then any brand of bottom bracket will work. 68 x 113 is a very common bottom bracket.