Tilton’s 7.25″ OT-II carbon racing clutches offer a unique combination of low inertia, high torque capacity, high heat capacity and smooth engagement characteristics. The carbon matrix plates (driven and floater) do not warp from heat, providing consistent shifting and minimizing heat-related clutch failures. The smooth engagement characteristics of the carbon plates provide excellent drivability and reduce shifting shock to other driveline components. Through the use of additional pressure plates (shims) and periodic rebuilds, 7.25″ OT-II carbon racing clutches offer a long-life option for the serious racer. These features make it ideal for the following applications:
- Road racing
- Endurance racing
- Short-course off-road
- Open-wheel/formula
Low Inertia
The moment of inertia for Tilton’s 7.25″ OT-II carbon racing clutches range from 52.26 lb-sq.in (.0153 kg-sq.m) to 74.85 lb-sq.in (.0219 kg-sq.m).
Lightweight
Tilton’s 7.25″ carbon clutches range in weight from 6.2 lbs (2.8 kg) to 9.1 lbs (4.1 kg).
Range of Torque Capacities
Tilton’s 7.25″ carbon clutches allow for a wide range of torque capacities, depending on spring color:
- 335 lb-ft (455 Nm) of torque/plate with Orange spring
- 410 lb-ft (557 Nm) of torque/plate with Gray spring
- 455 lb-ft (619 Nm) of torque/plate with Double Gray spring
- 495 lb-ft (673 Nm) of torque/plate with Triple Gray spring
Decades of Experience
Tilton Engineering invented the carbon/carbon racing clutch and patented the drive system in the 1980s. It was the first carbon/carbon clutch ever to win a Formula One Grand Prix (Ayrton Senna’s Lotus-Honda at the 1980 US Grand Prix in Detroit). Since then, Tilton carbon/carbon clutches have been continually refined to be the best carbon clutches on the market. They have seen multiple victories in races worldwide, from the 24 Hours of Le Mans to the Baja 1000.
Capitalizing on experience gained over the past decades, Tilton carbon clutches have evolved to become second to none in quality. Each is built using the finest materials, the latest in manufacturing processes and is held to strict quality control standards. As part of their build process, 7.25″ OT-II carbon racing clutches are rigorously tested and documented before being delivered to the customer.
2-Plate Specifications:
Weight**: 6.2 lbs/2.8 kg
M.O.I.** (Step): 52.81 lb-in2/.0155 kg-m2
M.O.I.** (Pot): 52.26 lb-in2/.0153 kg-m2
Pressure plate: Ultra-High Ratio
Spring Color | Torque Capacity
(lb-ft/Nm) | Release Load*
(lbs/daN) |
Orange | 670/911 | 560/247 |
Gray | 820/1115 | 680/299 |
Double Gray | 910/1238 | 760/334 |
Triple Gray | 990/1346 | 800/352 |
3-Plate Specifications:
Weight**: 7.6 lbs/3.4 kg
M.O.I.** (Step): 63.71 lb-in2/.0186 kg-m2
M.O.I.** (Pot): 63.16 lb-in2/.0185 kg-m2
Pressure plate: Ultra-High Ratio
Spring Color | Torque Capacity
(lb-ft/Nm) | Release Load*
(lbs/daN) |
Orange | 1005/1367 | 560/247 |
Gray | 1230/1673 | 680/299 |
Double Gray | 1365/1856 | 760/334 |
Triple Gray | 1485/2020 | 800/352 |
4-Plate Specifications:
Weight**: 9.1 lbs/4.1 kg
M.O.I.** (Step): 74.85 lb-in2/.0219 kg-m2
M.O.I.** (Pot): 74.30 lb-in2/.0217 kg-m2
Pressure plate: Ultra-High Ratio
Spring Color | Torque Capacity
(lb-ft/Nm) | Release Load*
(lbs/daN) |
Gray | 1640/2230 | 680/299 |
Double Gray | 1820/2475 | 760/334 |
Triple Gray | 1980/2693 | 800/352 |
* Values listed are typical for release bearings with the recommended 44mm contact diameter. Larger contact diameters will increase release load.
** Weight and M.O.I. include pressure plate, carbon floater plates, carbon discs and steel hub, and may vary based on your particular spline.
Tilton offers two different styles of every clutch configuration: one designed to be compatible with a step-type flywheel, and another for pot-type (“no-step”) flywheels. Step flywheels have a .100″ step for contact with the friction material of the clutch, so clutches made for this application will have a .100″ height difference between the bottom friction disc and the end of the clutch cover legs (the mounting points). Pot flywheels don’t have this step, so the friction disc and clutch cover legs will be flush on clutches designed for them.
Tilton uses a color system for indicating the angle and weight of the clutch spring, which has an effect on release load and torque capacity for the clutch. The exact values for each color vary depending on the type of clutch, so be sure to check the Specs tab to find exact measurements.
P65 Notice