While she still isn't back to 100 percent Duncan's knee is healing well and the strength will come back as she picks up her training loads.
"The knee is obviously a big one – it is a 5-6 month period that you are off the dirt bike so we wanted to get that done as soon as possible," she explained.
"It is going really good though. We have made huge gains on that lately. We have a bit of work to do – the prehab/rehab stuff that will never stop.
"As far as fitness on the bike goes – we have a lot of work to do having had six months off.
"I am going to have 5-6 weeks in total on the bike and I feel that is enough time to get up to speed. Obviously it is going to be a lot of hard work and long hours but I will be ready."
In 2016 Duncan was leading the world championship when she crashed into a photographer that was standing in the wrong place and injured herself, ending her hopes of winning the title. Then last year she avoided a pile up in the final round only to crash herself and have a post-race decision go against her that once again saw her miss the title.
But having had the best possible outcome with her rehab this year Duncan feels she is in a good space to make it third time lucky.
"I am just taking this year as a completely new start," she said. "I feel more motivated than ever. I feel I am in a good position so I am just looking forward to getting underway.
"With it being my third season I am no longer a rookie. I think I have learned a lot and gained a lot of experience in the good things and bad things that can happen."
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