Competition Clutch Lightweight Flywheel for Honda S2000

Competition Clutch Lightweight Flywheel for Honda S2000

At 11.5 lbs, the Competition Clutch ST flywheel (2-669-ST) is the one most S2000 owners should actually buy. It cuts real weight off the stock flywheel (the AP1 unit weighs about 14 lbs and the AP2 unit is over 21 lbs) while keeping the car completely livable on the street. You feel the difference in throttle response, rev matching, and shift quality without turning your daily commute into a workout.

Competition Clutch makes two S2000 flywheels: this ST lightweight at 11.5 lbs and the STU ultralight at 9.25 lbs. The ST is built for naturally aspirated, street-driven cars and pairs with stock, Gravity, Stage 1, and Stage 2 clutch kits. If your S2000 sees regular street miles, canyon runs, and the occasional track day, this is the better match. The STU is for dedicated track cars, forced induction, and Stage 3 plus setups where drivability trade-offs stop mattering.

What It Is and Why It Works

The flywheel is forged from 4140 steel with a one-piece integrated ring gear, then CNC machined and balanced to OE specifications. The one-piece ring gear matters: pressed-on ring gears can walk or shear under sustained abuse, and integrating it into the flywheel body eliminates that failure point while spreading heat more evenly across the friction face. The F20C spins to nearly 9000 rpm and the F22C1 is not far behind, so balance quality is not a footnote on this platform. It also meets SFI 1.5, the certification most sanctioning bodies want to see for track use, and the friction surface can be resurfaced at clutch time instead of the whole unit being replaced.

There is a common misconception that lighter is always better with flywheels. It is not. Go too light on a street car and you get rough idle, gear chatter, stalling in parking lots, and a car that fights you in traffic. Two decades of S2000 community experience lands on the 10 to 12 lb range as the sweet spot, and this flywheel sits in the middle of it. AP2 owners see the dramatic change, dropping almost 10 lbs of rotating mass, roughly 45 percent, off the crank: faster revs, quicker rev drop between shifts, sharper heel-toe. AP1 owners start from a lighter 14 lb baseline, so the gain is more subtle and the bigger draws are the forged construction and the SFI rating.

Specs

Fitment

One flywheel covers every year and trim of S2000, AP1 and AP2 alike. AP2 owners should know about the clutch delay valve built into the 2004-2009 slave cylinder. Honda added it to soften engagement with the heavy stock flywheel, and with a lighter flywheel it can make the pedal feel vague during fast shifts. Many owners swap in the AP1 slave cylinder (Honda 46930-S2A-003), a direct bolt-on that removes the valve and restores a mechanical, direct pedal. It is not mandatory; a mostly street-driven car can run the stock slave first and swap later if the feel bothers you.

What to Know Before You Buy

Expect the car to feel more alive immediately, especially coming from an AP2: faster revs, easier heel-toe, quicker rev drop on upshifts. Idle stays close to stock at this weight, but very mild gear chatter that was not there before is possible and normal. First gear takeoffs stay natural and passengers will not notice the swap. You will.

Who should buy it: street-driven and dual-duty S2000s, stock through Stage 2 clutches, occasional track days and HPDE, anyone who wants response without sacrificing manners. Who should not: dedicated track or boosted builds running Stage 3 plus clutches belong on the 9.25 lb STU instead, and an AP1 owner happy with how the car drives already has a reasonably light flywheel from the factory and can skip this upgrade entirely. Plan the install around clutch service since labor overlaps completely, source a release bearing separately because none is included, and have the mating clutch surfaces cleaned and the bolts torqued to spec with fresh threadlocker.