Hi,

On a 2015 Giant Defy Advanced, what BB do I need to convert it from the Shimano press fit that is in there to a gxp type and can run a SRAM crankset?

Thanks all.

Stu.

Bump for the lunchtime crowd.

I think you probably need BB86 bearings (86.5mm) for GXP cranks – something like this http://www.chainreactioncycles.com/sram-pressfit-gxp-alloy-bottom-bracket/rp-prod75586?gs=1&gclid=CjwKEAiAmNW2BRDL4KqS3vmqgUESJABiiwDToMthPrMz_tKQZIuqcqHVA7Ly3Rh9Xf2jB3dki7xk-BoCAezw_wcB&gclsrc=aw.ds

There used to be a company (bright line components?) that made a top hat style alloy cup that sat inside the bearing, a bit like the Hope GXP adapters, but designed for Shimano BB’s. No idea if they still exist.

I run a Hope one with the Hope adapters. Works fine.

Thanks Hob Nob

You may be able to use a top-hat bush to reduce the non-drive bearing side from 24 to 22mm on your HT2 BB – whether the Hope adaptor works is probably down to trial and error. Otherwise, simply fit a new GXP BB86