Originally posted by InitialD
I'm afraid changing to the 909518 Centax II clutch spring may make the situation worse. You could take even longer for the engine to engage the clutch ! The reason is that the 909518 Centax II clutch spring (1.8 mm diameter) is harder than the 6586 stock spring (1.7 mm diameter).
What I suggest is to loosen the Centax pre-adjusting nut (6583) until you get a decent clutch engagement without clutch slippage or without the engine revving too high. The 1.0 mm setting can be a little too much for some engines to engage the clutch.
Note that you do not have to take off the clutch bell to be able to access the Centax pre-adjusting nut. You can adjust it externally by inserting a 1.5 mm allen into one of the 2 holes on the clutch bell and catching one of the 2 grooves on the pre-adjusting nut.
Once that is done and the pre-adjusting nut held firmly externally by the 1.5 mm allen, turn the flywheel CLOCKWISE to loosen the pre-adjusting nut to get earlier engagement and ANTICLOCKWISE on the flywheel to tighten the pre-adjusting nut to get a later clutch engagement. You want to turn the flywheel CLOCKWISE.
Master would you consider changing to NTC3
then we can both go bite crash1