On Friday, February 20 the whole family will compete in the Skyline Sprint Warrior event.
This is a gondola-accessed race on a tricky downhill course on Mt Ngongotaha.
"Sacha and Jake may be little kids on little bikes, but from what we've seen they've got talent and skill to burn," said Sprint Warrior organiser Tak Mutu.
"We think they might just give some of the grown-ups a tune-up."
The opening weekend of the festival is headlined by the New Zealand National Mountain Bike Championships.
The cross-country will feature Canterbury's Anton Cooper, who won the junior men's cross-country title at the 2012 UCI Mountain Bike World Championships in Austria.
Cooper will defend his New Zealand title in the cross-county on Saturday, February 15.
The next day, Brook McDonald will defend his national downhill title on the dramatic and demanding Taniwha trail. The popular rider from Hawke's Bay is known as "The Bulldog" and won the Junior Men's World title at the UCI Mountain Bike Worlds in Canberra in 2009.
Another popular Kiwi rider, Cameron Cole from Christchurch, returns to competition in the downhill, after a big crash last year. Cole won the junior men's downhill title in front of a raucous home crowd when Rotorua hosted the UCI Mountain Bike World Championships in 2006.
Garth Weinberg is another local who won a world title in front of cheering home crowds.
Weinberg will compete in the National Mountain Bike Championships.
See the festival programme at www.rotoruabikefestival.com with regular updates at facebook.com/RotoruaBikeFestival.