A sell-out crowd saw Hahn finish 10th in Saturday's opening night for round five of the series, before improving to seventh in Sunday's sixth and final round of the season.
It was a result that saw the American import tie on points for third in the standings, but was awarded fourth overall on count-back this evening. He announced he will retire from fulltime professional competition ahead of 2017.
"It was an up and down weekend for sure!" Hahn explained post-race. "I lost a lot of points last night unfortunately, but tonight I rode good and made some points back. The main event was pretty chaotic, but to have the opportunity to come over here and end my career in Australia is really cool.
"I didn't feel like I was aggressive enough this weekend, I probably should have laid into some people when I didn't, although it was still good racing and it was the best round of the year, for sure. It was tough for passing, you had to get good starts, but I enjoyed it a lot and have to say a huge thank you to National Pump Monster Energy Kawasaki Racing Team."
Wil Hahn, 2016 Australian Supercross Championship, AUS-X OPEN
Teammate Mosig rode his KX450F to an impressive fifth-place finish on Saturday, going up against increased international competition this weekend in the Sydney spectacular, but was unable to make it through to the 12-rider main event on Sunday.
Despite a difficult final round this afternoon, Mosig was able to claim sixth overall in the championship after a hard-fought six rounds across the country.
"It's been a little bit of a struggle this supercross season, so it was good on Saturday to turn it around and finish fifth in the final," Mosig said. "That was my best of the season, but today I didn't get a clean run through the heat or semi, then in the last chance I gave it everything and wasn't good enough - that's the sport we're in and it can be tough.
"I'm happy with sixth in the championship though, even if it wasn't what I set out to do, but at the end of the day I was there until the end and finished another season. Thanks to all of my supporters, National Pump Monster Energy Kawasaki Racing Team and everybody behind us."
Kade Mosig, 2016 Australian Supercross Championship, AUS-X OPEN
Retired four-time Monster Energy AMA Supercross Champion Ryan Villopoto made a great return to the sport in a one-off appearance pitted with the Australian factory-supported Kawasaki squad, going 6-4 in the AUS-X Open.
Kawasaki Motors Australia and the team would like to thank Wil Hahn for the tireless effort, diligence and showmanship that he delivered during his time as a factory racer under the National Pump Monster Energy Kawasaki Racing Team banner and we wish him all the very best with his future endeavours!
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