INDIANAPOLIS — Following a crash at the 2023 Indianapolis 500 in which Kyle Kirkwood's rear tire flew over the catchfencing and on to a woman's car, the NTT IndyCar Series and its chassis partner Dallara have announced a new rear-wheel bearing retaining nut will debut this weekend at the doubleheader at Iowa Speedway.
After an intense review of the tether system used to keep tires from flying off the cars, IndyCar determined that the Zylon material it uses for the tethers did not fail, but instead broke due to an "unusual and never experienced set of circumstances."
The upgraded wheel nut is being distributed to all entries for this weekend's races. Series officials said the strength of the new rear-wheel bearing retaining nut has been increased by 60% over the design used at May's Indianapolis 500.
“It is Dallara's mission, along with INDYCAR and all of the racing series we work with, to maintain and continuously improve safety based upon the highest standards,” Dallara CEO Stefano dePonti said. "We have developed and produced new components that will increase the strength of the corner in case the unlikely sequence of events repeats itself.”
The errant tire that prompted the upgraded part notably affected Robin Matthews' 2012 Chevrolet Cruze — affectionately named "Snowball" — when it landed the car's hood during the 2023 Indy 500. The Indianapolis Motor Speedway, along with the IndyCar Series, invited her to "kiss the bricks" following the race and replaced her damaged car with a brand new one.
The new wheel nut upgrades are not expected to impact the racing quality, but rather they are expected to prevent errant tires in the event of similar circumstances.
You can watch this weekend's Hy-Vee IndyCar Race Weekend Doubleheader live on WTHR Channel 13.