Wipeout Wiki

The Gears of Doom is an obstacle in the Wipeout Zone of Season 2. It consists of three large rotating gears that must be traversed. Seeing as one of the first and most difficult obstacles ever, after at least one wipeout, contestants can either try again or move on and take a time penalty.

In episodes 6 and 16, the gears had teeth on them.
In episode 9, the gears were covered with trampolines.