"That cost me plenty and it meant I had to spend the whole season playing catch-up in the points. I was creeping back up the points when I broke a bone in my foot. You could say I had an inconsistent start to the year."
But the second half of his season was certainly consistent and in all the right ways.
"I was the only rider to finish on the podium at both the final two rounds. It was good to close out the season in second spot so, overall, it was not such a bad year in the end. I have the same sponsors in place for next year - AmPro Yamaha and Monster Energy - so I have the support I need to get the job done."
He is already starting to build up for this season in America by running, cycling and swimming, as well as riding his Yamaha YZ450F whenever he can.
"I know I can again expect stern competition from Kailub Russell, Cory Buttrick and Charlie Mullins, but it's a tough competition and anyone can threaten."
Whibley is a four-time consecutive winner of the parallel Off-Road Motorcycle and ATV (OMA) series in the US and he begins that title defence at the end of this month.
However, it's the GNCC title he craves most and that campaign starts in Florida on March 13.
Whibley is also supported by Sargent Yamaha in Masterton, MotoSR suspension, BikesportNZ.com, Graphic MX Creation and Yamaha New Zealand.