Confused. Building bike. Have set of lovely barely pre-loved bits from a mate. In the cranks box is a RF DH RACE BB and a set of respond cranks. Fitted BB, went to put NDS Crank Axle in. Doesn’t fit. Can’t clear the BB cups. Whipped out the NDS cup to test, nope goes in about 20mm and stops on the silver bonded thing you can see on photo.

Bike Build by Alex Leigh, on Flickr

Dug out an old hope BB and it slips through there no problem. Reading up a bit on DH BB, it does seem to have some odd things going on but I couldn’t find a compatibility chart.

Worse case I stick a new BB In there. No drama, but interested if anyone knows what’s what ?

Scratch that. A light malletting sorted it!