Does anybody know if the croosmax xl front hub can be converted to 15mm bolt thru?

Think it might be 20mm only but also interested to know

Probably just 20mm adapters. I doubt they were thinking about 15mm when they were in production – which they haven't been for a few years now.

Theoretically possible, as they can take a 20mm axle, but you'd have to get the 15mm adaptors made up yourself.

Mate runs them 15mm he had the qr caps machined out to fit. Works a treat 😉