Put my 54t on my TT bike and recalibrated the Quarq using Qalvin and a known weight. Raised the slope by 1.27%+. The zero offset changed from -170 to +34. According to Quarq, the zero offset change is okay and due to the changing of the ring i.e. loosening and tightening of chainring bolts. It is okay as long as it does not vary by 50 units from the start to the finish of the ride.

Fudgy will still kick my ass (a lot) on Saturday. So it goes.