Clutch Masters 725 Street Twin Disc Clutch for RSX/Civic/TSX K Series

Clutch Masters FX725 Twin Disc Clutch Kit - K-Series (7.25" Street & Race)

This is the top of the K-series clutch food chain. A 7.25 inch twin disc built from decades of drag racing development, designed to hold serious horsepower and torque while keeping pedal effort reasonable enough that you can actually operate it. If you've outgrown single disc clutches or you're building something that makes real power, this is where you end up.

Be Honest About Street Use

Clutch Masters is upfront about this and so are we. The FX725 is focused on drag racing, and the minimal rotational mass that makes it so effective on track is exactly what makes it less than ideal as a daily driver clutch.

That said, friction material has come a long way, and this Street and Race configuration is specifically built to handle occasional street driving. So if the car sees the road between track outings, it'll do that. What it won't do is be pleasant in stop and go traffic every morning. Buy it knowing which side of that line your car lives on.

If your car is genuinely a daily that occasionally sees a track day, you want a single disc setup instead. This is for the build where performance comes first.

Why Twin Disc Instead Of Single

Two discs means twice the friction surface, and that changes what's possible. You can hold dramatically more torque, and because the load is spread across two surfaces, you get that capacity without the brutal pedal pressure a single disc needs to hold the same power. That's the whole appeal: enormous holding capacity that you can still modulate.

The smaller 7.25 inch diameter also cuts rotational mass significantly compared to a full-size clutch, which means the engine revs faster and gear changes happen quicker. On a drag car that's time. The 7.25 size also fits the smaller bellhousings on these transmissions, which is why it's the twin disc for K-series rather than a larger race unit.

The Billet Cover Is Where The Money Goes

This is the part that separates it from cheaper multi-disc setups, and the numbers make the case. The cover assembly is machined from billet aluminum and Type 3 hard anodized, with roughly 25% more tensile strength than a competitor's cast unit.

What that buys you is consistency. A billet cover flexes about .003 inches under load. A cast or stamped cover can flex as much as .030 inches, ten times as much. That flex is wasted motion, because every bit of travel your throwout bearing spends bending the cover is travel that isn't engaging or disengaging the clutch. Eliminate it and your pedal does exactly what you asked, every time, which matters enormously when you're staging a car or shifting at the limit.

The stiffer cover also delivers more clamping force over the same surface area, so you're holding more power with a clutch that's easier to drive.

The QR System Is Why It's Quiet

Multi-disc clutches have a reputation for rattling, and it's earned. Clutch Masters addresses it with their Quick Release pressure plate, which is unique to their multi-disc kits.

Three spring-loaded bolts let the pressure plate engage and disengage evenly and smoothly, and the result is up to 50% less internal clutch noise and chatter. That's a meaningful difference if the car ever leaves the track, and it's the single feature that makes a twin disc tolerable outside of a race environment.

What's In The Street And Race Configuration

This TD7S setup runs one ceramic rigid disc and one fiber tuff rigid disc. That combination is deliberate: the ceramic disc provides the aggressive holding capacity, while the fiber tuff disc smooths out engagement enough to make the clutch drivable rather than purely on-off. It's how you get race holding power with manners.

A steel flywheel is included, machined from a 1045 billet core and black oxide treated for rust prevention.

Fitment

• 2002-2006 Acura RSX Type-S, 2.0L 6-speed
• 2002-2006 Acura RSX, 2.0L 5-speed
• 2006-2010 Acura CSX Type-S, 2.0L 6-speed
• 2004-2008 Acura TSX, 2.4L
• 2009-2014 Acura TSX, 2.4L 6-speed
• 2013-2014 Acura ILX, 2.4L 6-speed
• 2002-2011 Honda Civic Si, 2.0L 6-speed
• 2002-2010 Honda Civic, 2.0L 5-speed
• 2012-2015 Honda Civic Si, 2.4L 6-speed
• 2003-2012 Honda Accord, 2.4L

Who Should Run The FX725

This is for the K-series build that's outgrown everything else. Drag car, dedicated race car, or a serious street/strip build making power a single disc can't hold. You're getting drag-proven holding capacity, a billet cover that doesn't flex, and the QR system keeping it civil enough to live with between events. If your car is primarily a daily driver, step down to a single disc. If it isn't, this is the answer.

Fits: K-series applications listed above. Type: 7.25" (184mm) twin disc, Street and Race (TD7S) configuration. Discs: one ceramic rigid, one fiber tuff rigid. Cover: billet aluminum, Type 3 hard anodized, approximately 25% more tensile strength than cast, roughly .003" flex versus up to .030" for cast or stamped. Features: QR quick release pressure plate, up to 50% less internal noise and chatter. Flywheel: 1045 billet steel, black oxide treated, included. Best for: drag racing and race applications, occasional street driving.