Over Labour Weekend, he raced in the 2020 MX Fest in Taupo, where he crashed in his first race and was unable to finish the day's racing.
He has bounced back from the crash well and will be close to full fitness this weekend.
Murphy will also be racing in the 6-8yr MX 50 class on his LMC Husqvarna 50cc.
Jack raced in the same class as a six-year-old at last year's mini nationals in Hawke's Bay and qualified for the main event, finishing 24th overall.
His goals for the weekend this year are to get good starts, secure one of the top 30 spots in qualifying, and to finish in the top 15 overall.
With huge numbers in their class, both boys will need to qualify in the top 30 to race this weekend in the main championship event. Qualifying position is determined by lap time.
After the qualifying round, the weekend consists of five 10-minute races across the two days.