The reason the bikes slip in higher gears is due to a higher load on the engine in those gears. In the lower gears you have much more mechanical advantage over the wheel so the "load" placed on the engine isn't as high. Essentially the slower a motor revs up at open throttle the more load. The quicker it revs the less the load.
If you were really riding hard and opening it up big in lower gears you would notice slip there also.

NOw. I recommend you replace the entire clutch pack including springs.
The amount of grip that the clutch exerts on the plates is related to the height of the clutch "stack". IF you use older plates they are already worn and will reduce the stack height and reduce spring preload and thus reduce clutch grip. And you will have a slipping clutch much sooner than the original clutch.
Also the springs can sag a little and they are cheap. Stick with stock. After market "heavy duty " springs are not necessary and will cause un due rider fatigue and wear in the clutch.

On mildly used machines(ie not a race bike) it shouldn't be a problem but I would closely inpsect the outer clutch basket for grooving. It will cause grabbiness and other problems.


IF you need some parts just e mail me. todd@zenengines.com

Thanks,
Todd Bellew


[This message has been edited by Todd Bellew (edited 09 July 2003).]

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Thank You,
Todd Bellew