Also available as a large upgrade kit with clutch basket (BGM0190).
This evolutionary stage of our popular HD primary kit now consists of only two components, greatly simplifying installation compared to the old version with loose sleeves and two cover
plates.The kit does not fit the springless primary wheels of the 50cc models. Since these should also receive a longer gear ratio when the displacement is increased, the installation of the upgrade kit in a new primary reduction is possible without any problems.
In principle, such an upgrade kit should be used in any engine, not only in very powerful engines. The enormous torque of today's engines also demands the use of reinforced shock absorber springs. This prevents the too soft series springs from going on block and the lugs of the clutch linings from working their way into the basket.
Note: Depending on the manufacturer and tolerances of the primary used, it is possible that the CNC cover plate touches the bearing seat or its strut of the crankshaft bearing.
In this case, either distance the primary using spacers (see 'Accessories') or grind a slight radius on the bearing seat of the engine housing.