User guide
Tilton Engineering invented the carbon clutch and patented the drive sys tem in the mid 80’s.
Tilton also holds a patent on its pressure ring locating system, which is unique to Tilton carbon
clutches. Tilton’s carbon clutch was the rst ever to win a Formula One Grand Prix (Ayrton
Senna’s Lotus-Honda at the 1987 US Grand Prix in Detroit). Since that time Tilton has produced
thousands of carbon clutches, with multiple victories in races worldwide, from the
24 Hours of Le Mans to the Baja 1000.
The patented Tilton Carbon (C/C) clutch provides the best combination of light weight, low
moment-of-inertia, smooth engagement, and durability. It is also an excellent value when
properly maintained. Every Tilton carbon clutch follows the same rigorous build, test and
docu mentation process. Each clutch is tested for clamp load, torque capacity, and release
characteristics and every component within an individual clutch is recorded in our database.
Tilton maintains a le on every C/C clutch they build. This le includes all of the original build
and testing information and all service/rebuild history performed by Tilton. Save the build sheet
provided with the clutch. It includes critical maintenance information.
INSTALLATION
1. Proper alignment of the input shaft with the crankshaft is critical for long clutch life. Use the
following procedure if your gearbox uses a separate bell housing. Bolt the housing onto the
engine. Place a magnetic base dial indicator on the end of the crankshaft. Sweep the trans-
mission register diameter on the inside of the back of the bell housing.
Total Indicated Runout (TIR) must not exceed .010". Sweep the back face of the bell housing
at a 6" (152 mm) diameter. The TIR in this position must not exceed .010".
2. Install a new pilot bearing. A prematurely worn pilot bearing indicates a bent input shaft or
an input shaft that is otherwise not properly aligned.
Misalignment can be caused statically (see Step 1) or dynamically, like when the weight of
an unsupported gearbox causes a weak bell housing to ex under racing conditions.
3. The drive hub should slide smoothly on the input shaft. An application of
anti-seize compound is acceptable if very little is used.
4. The drive hub can usually be installed in one of two directions. The clutch will work either
way as long as the hub clears the ywheel bolts and the hub’s splines fully engage the input
shaft splines. The hub will move towards the ywheel as the clutch wears.
5. With the ywheel bolted to the crankshaft, place the clutch on the ywheel. Using an align-
ment tool or spare input shaft, align the hub. Tighten the bolts in a star pattern turning each
one less than one full revolution at a time. 5/16" and 8mm bolts should be torqued to
18 lb-ft with thread locking compound. Threaded aluminum ywheels may require less
torque to prevent stripping the threads. Once the bolts have been tightened, the diaphragm
spring ngers should appear nearly at. If the ngers appear to be inverted, you may not
have the proper pressure plate installed in the clutch or the pressure plate may not be
seated in the top oater plate.
6. Set the bearing clearance. If you are using a Tilton hydraulic release bearing the recom-
mended clearance is .170"–.230" (4.3 mm–5.8 mm). Depending on your particular clutch
conguration, the bearing clearance loss will be four to ve times the amount of the clutch
wear. You need to have enough bearing clearance to allow the full wear range of the clutch.
7. When installing the gearbox, do not allow its weight to be supported by the clutch.
8. The clutch diaphragm spring must not be stroked beyond the maximum amount listed in
Table 1. A pedal stop may be required to prevent damaging the clutch (Diagram 1).
Overstroking the clutch during the bleeding process can be prevented by applying a light
force to the pedal and opening the bleed screw before stroking the pedal. Close bleed
screw before pedal is returned to it’s original position. Master cylinder sizing recommenda-
tions are also listed in Table 1.
Table 1
...Tilton’s carbon clutch
was the rst ever to win a
Formula One Grand Prix
(Ayrton Senna’s Lotus-
Honda at the 1987 US
Grand Prix in Detroit).
5.5" (140 mm) and 7.25" (185 mm) Carbon Clutches
INSTALLATION INSTRUCTIONS
98-1300
Carbon Clutch size: 5.5" 7.25 "
Realease bearing contact diameter
(radius face).
38 mm 44 mm
Maximum stroke of clutch
diaphram spring.
.200"
(5.1mm)
.250"
6.4 mm)
Recommended master cylinder
bore* when using Tilton hydraulic
release bearing.
5/8" 3/4"
Theoretical maximum master
cylinder stroke** with
recommended master cylinder.
.840"
(21.3mm)
.730"
(18.5 mm)
* Except: sprint, midget, & silver crown package
**Assumes .040" cut-o port travel.