Mother-Daughter Racers Breaking Snowmobile World Records for That Girl Racing

The track is twisted, with jumps, sharp turns and hairpin curves. The snocross circuit is demanding on racers, allowing no room for distraction. There is no doubt that the mother-daughter relationship is also demanding and powerful. Tiina Duncanson is the mother, Kiersten Duncanson is the daughter. They are That Girl Racing and both are world record grass drag racers.
Snowmobile Racers Kiersten & Tiina Duncanson of That Girl Racing
Snowmobile Racers Kiersten & Tiina Duncanson of That Girl Racing
“My daughter and I were racing in a professional competition when her sled came up hard,” said Tiina. “For a moment I wondered if I should let off the throttle and go back to her, only for a moment.” Tiina decided to race. “It’s that competitive mother instinct, I finished the race and I won.” Kiersten was okay and would have been mad if Tiina stopped. Tiina also said she knew her husband Peter was right there.

These races test the maneuverability and acceleration of the machines, while putting the skill, agility and balance of racers to the test. The next snowmobile race for That Girl is the Canada-USA Championship at St.George de Beauce in Quebec. Some say this is where ice drags began. It is a split event over two days of racing with regular points. The challenge is American vs. Canadian. “I’ll drive my 800, with the K&N filter (RU-1480),” said Tiina. “If you can’t keep the pistons alive you can’t win and if I didn’t have my K&N filter there would be no way.”

Snowmobiles are sold with an air box and not an air filter. Extreme riders and racers remove the air box which leaves them with no protection. To compete, they put a filter on to aid in filtration. It’s necessary in grass drag racing to keep dust and grass strands out of the motor.

“In grass drag racing you have to have a filter,” said K&N Engineering Powersports Brand Manager Johnny Jump. “Without a filter all those grass particles and dust will get into the engine, scar the pistons and tear the motor apart.” As the sides of the skirts of the pistons get worn down from dust and contamination, it breaks down the seal the piston has within the cylinder, said Jump. “Less seal means less compression.”

Tiina said anybody who is anybody on the circuit runs a K&N. “I watched another brand, with a green filter collapse on the course,” she said. “The K&N filter keeps the dirt and snow out of my engine.”

Tiina is known as “That Girl” and Kiersten, 18, is known as “That Other Girl.” Tiina got into the grass drags around 1997. “My husband, Peter used to show antique sleds and that went hand-in-hand with the grass drags,” she said. “I wanted to race and he figured I'd be over it in no time, not so.” Now Peter Duncanson is in the racing business 24-7, said Tiina. Peter keeps the machines running and is the crew chief.

Kiersten began racing at the age of 12. Tiina taught her to drive and to pick lines on the track. “My daughter and I are like mirror images, “said Tiina. “Kiersten is number 721 and I’m 127.”

“Kiersten turned pro when she was 14-years-old,” said Tiina. “We pulled her out of the junior division and put her in the pro-division because she was winning everything.” It didn’t take Kiersten long to prove herself on the pro circuit. Kiersten broke Tiina’s world record three years ago, said Peter. “She did 5.2 seconds @ 93 MPH in the 500 open-modified.”

That Girl Racing uses K&N filter part RX-4140 on the 1000 and SN-2620 and SN-2510 in snocross, said Peter. RX-4140 is a K&N XStream filter, it works well in the 1000 because air can go into the sides and through the top of the filter and you also gain filtration.

“On the 1000 open-mud I have a three year world record,” said Tiina. “Every year I’d break it by dropping the notch a littler farther.”

That Girl Racing will have a new sled for the World Series in Sault Ste Marie, Ontario. “We’re always keeping up with the latest technology,” said Tiina. “It’s great to be a female driver with the fastest sled in the world!”

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