The 34-year-old former Manawatu forestry worker won two major cross-country titles in the US during that time, clinching the Grand National Cross-country Championships and the Off-Road Motorcycle and ATV crown as well.
The start of Whibley's latest US race was scheduled for noon but temperatures hadn't moved much above freezing point and parts of the ground, in a few spots on the hillside, was still frozen rock hard.
Whibley said he struggled through most of the first lap. "It was so cold that my eyes kept watering with the cold air and I could hardly see where to go."
Come the second lap and Whibley got a flat rear tyre. Since he was riding his practice bike he hadn't fitted any "tyreballs", and that was a concern as the track had turned up a lot of sharp-edged rocks after the quads had raced there the previous day.
Even with the flat tyre, however, Whibley managed to stay ahead of his closest rival until about 1600m from the finish where he lost the lead after a small bottleneck formed and second placegetter Jesse Robinson found his way past.
Coming into the exchange area, Whibley's partner Nix went out and gave chase to Robinson's partner Casey Leatherman.
Nix regained the lead but then surrendered it again, meaning Whibley came into the action with a few seconds to make up. That he did quickly and, after three more laps, he had established a good lead which was further extended when Nix took over for a second time.
Whibley's focus now is preparing for the start of the GNCC and OMA competitions.
