gt bottom bracket

[weeman_mtb]

Drystone has the answer....you can still fit a smaller 68mm BB into it but it needs to be a 73mm shell. The result would be crank arms very close or catching.

Even if the cups go in the spindle is still 113mm in length regardless whether it's a 73 or 68mm wide BB shell. How will that solve anything. If it hits on a 113 width doesn't matter now does it. Bottom line is it will need to be longer to clear and work properly.

Threading a 68mm BB into a 73mm BB shell is not the right thing to do either and hugely poor advice. If it's a 68mm BB with a shoulder on one side it will throw the hole thing off one direction once installed....bad, bad advice. Is this to be a wall hanger or a rider?

He's not suggesting to do it, just merely stating that if it is a 73mm frame then a 68mm bottom bracket would go in and tighten up and cause this problem on the left hand side.

 

[rigbob]

bottom bracket

thanks for all the replies ,really apreciate it ,have just measured the shell its 73mm ,but i think if i get a 73 113 it will still catch i think i need a 73 118

 

[weeman_mtb]

It might do it might not, but the frame being 2.5mm wider at either side would have been the cause of your crank catching when you stuck a 68mm bb in.

 

[weeman_mtb]

To further add, I have just checked my spares and have an M443 crankset that was supplied (from ebay) with a 118mm bottom bracket. These were supposed to be taken from the same bike and I have no reason to believe otherwise.