Cosmetic scrapes/scuffs. Light rust on flywheel surface.Only for 1/2009 and later production with 6-bolt crankshaft
The Clutch Masters FX850 kit is a light weight and highly capable clutch and flywheel package for mixed track and occasional street use on E82 135i/1M, E9X 335i, and Z4 35i. The FX850 Series has a higher holding capacity, less clutch chatter, and a smoother engagement compared to the FX725 Series. And the FX850 series Twin Disc will accept one sprung disc creating a slightly smoother engagement compared to the two rigid discs used in the FX725 clutch.
Twin Disc Clutch & Flywheel Kits were originally developed for muscle car drag racing - extremely high torque and hard launches. The materials used in the CM FX725 and FX850 clutches are able to hold a lot of torque (much more than any naturally aspirated BMW will produce) and will stand up to a lot of abuse. This also makes them ideal for drifting and clutch kicks where strength and quick engagement are critical. The pressure plate design in a Twin Disc eliminates the drive straps used on a traditional clutch, which is the most common failure on drift clutches.
Twin Disc clutches also offer cost savings in the long run. Not only do the clutch materials and pressure plate hold up better under extreme conditions but the consumable cost is lower than OEM and sport Clutch & Flywheel Kits as well. Clutch discs and friction plates are typically under $200 and they can be replaced without the need for special tools.
Features of the CM FX850 kit:
- 8.5" Twin Disc setup reduces weight without giving up friction surface
- Mixed ceramic and fibertuff (organic) clutch materials - street friendly with high torque rating
- 8.5 sprung-hub is more street friendly than FX725 kit
- Stronger and more reliable billet aluminum cover (does not use failure-prone drive straps)
- 6061-T6 aluminum flywheel
- 22lb total weight - improves throttle response and reduces driveline loss
- Upgraded throw out bearing included
- Cost effective and replaceable consumable items
- Made in USA
Clutch Masters is at the forefront of clutch design and technology. This Twin Disc clutch for the E82 135i/1M, E9X 335i blends advanced friction materials with race technology to give you a clutch upgrade that keeps pace with your upgrades. This Track/Street Clutch & Flywheel Kit uses ceramic and organic-based clutches to achieve high torque ratings with some clutch slippage. They are designed to hold tremendous horsepower and torque ratings, while being reasonable to operate on the track with occasional street use. By increasing the clamping force of the pressure plate and adding to the square inches of usable disc area, CM Twin Discs significantly increase clamping values with an average of 50% increase in pedal pressure depending on the application (pedal pressure only seems high because of the ultra-light stock clutch feel). The clutch cover assembly is CNC machined billet aluminum with 25% more tensile strength than the competition’s cast unit. CM covers do not use straps so a known weak point on OEM clutches is eliminated.
The 9lb flywheel is machined from billet 6061–T6 aluminum to meet SFI spec 1.2 for competition in NHRA, SCCA, and NASA. This is a single-mass flywheel that will replace the failure-prone stock dual mass. More noise and chatter is to be expected given this kit's intended use and design (but we found it livable). Clutch noise will improve after the break-in period. Each aluminum flywheel includes a replaceable friction surface. Steel flywheels are also available on select applications that have less noise and better drivability.
“Street and Race” (TD8S) – 1 ceramic rigid disc, and 1 fiber tuff sprung disc
“Race” (TD8R) – 1 ceramic sprung disc and 1 ceramic rigid disc
We consider "street use" to mean that the clutch can operate on the street but it does not imply use as a daily driver or regular street use. The intended use is for track, drift, and racing and the materials and design have been optimized for that. We assume the operator can tolerate greater levels of noise and vibration as well as shortcomings in driveline smoothness and engagement.
To read more about clutch design and selection, read our Tech Topic page by clicking here.
BMW Fitments: 1 Series
E82 / E88 (08-13) > 135i
E82 / E88 (08-13) > 135is3 Series
E90 / E91 / E92 / E93 (06-13) > 335i
E90 / E91 / E92 / E93 (06-13) > 335is
E90 / E91 / E92 / E93 (06-13) > 335xiZ Series
E89 Z4 (2009-2016) > Z4 sDrive35i