American Ninja Warrior 8
The Fly Wheels served as the 3rd obstacle in Indianapolis Qualifying of American Ninja Warrior 8. Competitors would have to swing across 3 hanging wheels with a 1-inch ledge on either side. The 2nd wheel was higher than the other two wheels, so competitors would have to make sure their momentum got them high enough to grab onto the small ledge on the second wheel. After the second wheel, competitors would have to maneuver their way onto the 3rd wheel, which was on a pendulum and therefore would swing back and forth, but the wheel itself did not spin.
This obstacle proved to be quite difficult as numerous ninjas who tried it failed to swing their away across, typically due to weak momentum. There was also a slight disadvantage with its placement after the Rolling Maruta, in which some athletes may have fell due to dizziness and/or lack of focus. A total of 25 competitors fell on the obstacle. This was also the farthest any of the celebrity racecar drivers got to.
In the city finals, the third wheel was removed, creating a far longer dismount. Three other competitors consequently failed this obstacle.
American Ninja Warrior 9
The Fly Wheels reappeared as the 3rd obstacle in the Los Angeles course. During the Red Nose Day Special, four out of the nine celebrities attempted the obstacle, with three of the four (Nick Swisher, Ashton Eaton, and Stephen Amell) completing the obstacle on their first try and the fourth (Derek Hough) falling on his first attempt but trying again and succeeding the second time. During the qualifying round, 20 competitors failed the obstacle.
- Compared to most cities, the Fly Wheels is an upper-body obstacle despite being the 3rd obstacle. The upper-body and lower-body obstacles between the 3rd and 4th obstacles were switched in Indianapolis, as the Disk Runner is a lower-body obstacle. It continues this deviation in American Ninja Warrior 9, with Block Run being the 4th obstacle.
- This obstacle is also one of the few obstacles where bending your arms at a 90-degree angle is not recommended. In this case, putting your arms straight on the fly wheels gives you more momentum to swing to the next wheel.
- It's somewhat similar to the Cycling Road and Flying Shelf Grab.