CLUTCH REMOVAL
Remove the Starter Nut. Note: Special clutch holding spanner is designed to fit around the drive hub to prevent the crankshaft from turning. Do not hold with the ignition nut end. Remove the External Thrust Washer, Drum, Roller bearing and internal Thrust Washer. Remove securing nut & Coned Safety Washer. Remove the Clutch Drive Hub only using the
special Clutch Puller tool. Remove the Woodruff Key from the crankshaft.
MAINTENANCE & REPAIR
Due to the extreme demands of racing, it is important to properly maintain your clutch in order to obtain maximum performance and reduce risk of clutch breakage.
Roller Bearing
Since the Formula TKM Clutch is a dry clutch, there is no oil supply for the bearing. It is necessary to ensure that the bearing and thrust washers are lubricated with the recommended Slick 50 grease at all times. The bearing should be replaced whenever the drum is replaced.
Sprocket/Drum Assembly
Oiling the chain before each track session will increase the life of the sprocket. A worn or chipped chain should be replaced as it will quickly wear out the sprocket. The sprocket should be replaced when the teeth are worn or
hooked. For maximum sprocket life use a long chain with the engine set forward. This will maximise the number of teeth engaged.
Friction Disc
The Friction Disc has a steel core with ceramic friction material bonded to the surface. It should be inspected after two hours of use. Replace if friction material is cracked or worn below 2.90mm thick. It should give many hours of use.
Springs
The springs are made from stainless steel. They will last many hours and only need to be replaced when broken or collapsed below 12mm free length.
Pressure Plate
The pressure plate is precision ground on the surface that engages the friction disc. This surface should be checked periodically for warpage and wear. Replace when badly warped or worn.
Drive Hub
Remove the levers from the drive hub, check for wear in the slotted area. Badly worn slots will cause poor performance.
Levers
The pivot hole in the lever is subject to stress due to frictional loading from centrifugal force. This causes the pivot hole to eventually elongate. Inspect the levers for pivot hole wear whenever you rebuild the clutch.
Dowel Pins
The dowel pins must absorb high stress from the levers. Replace as part of a major clutch service.
CLUTCH ASSEMBLY
Clean parts with disc brake cleaner. Disc brake cleaner comes in an aerosol can and is available at most automotive parts stores.
Do not use petrol to clean the clutch!
Apply anti-seize copper slip to the dowel pins. Slide dowel pins into the levers. Insert into the drive hub assembly. Insert pressure plate onto the drive hub. Use a small quantity of copper slip on the triangular corners to ease movement. Place each spring over a corresponding pressure plate stud. Apply Blue Loctite 243 to threads of spring retainer. Next screw the green retaining nuts onto each stud until just tight. Torque to 2/3 lbs/ft. Check that the distance from the top of the retaining nut to the drive hub face is 6.25mm +- 0.25mm. Lay the friction disc onto the flat side of the pressure plate. Place the fixed plate over the drive hub and align the 3 holes in the fixed plate with the drive hub holes. Apply anti-seize copper slip to screws and insert into the bolt holes in the hub. Tighten screws to 1 lbs/ft. Note these screws should not be over-tightened or they will be difficult to remove.