Using 30mm spindle cranks with press-fit BB92 bottom brackets involves a few easy steps:
- Step 1: Ignore most of what's written on the internet about how you can't get this to work.
- Step 2: Get hold of the BB92 x 30mm BB kit from Real World Cycling. This uses specially developed bearings by Enduro that press into the BB92 shell. Each bearing features a double row of balls for strength and longevity (because the balls themselves have to be so small because of the large diameter spindle).
Slight caveat
To work best you want to use a 30mm spindle crankset that has a sufficiently wide axel. Cranks like the Specialized S-Works MTB cranks (and road variants) will NOT work with the Enduro bearings on a BB92 bottom bracket because the spindle is not long enough.
Cranks like the Canondale Hollowgram will work if you get the right length spindle. I was able to use a 125mm long spindle on my Trance X 29er frame but I did have to machine the lip off the axle. Longer (and more common) axles like the 131mm and newer 132mm will work as they are wider but you will need to use spacers on either side.