Above is a pic of 3 different sets of wave washer, seat, and #6 drive plates. These were oem to their perspective bikes and were replaced due to shudder. Ths post is for the doubters and "type of oil" solvers and for those who just want to know. The doubters---this is for real and evryone will experience this at some point (wether you admit it or not). The "oil type" guys, well if no oil is ever getting to these parts and the ajoining clutch plates (fibers/steels), then how does the type of oil ever going to matter. The pics below show the damage to the #6 plate from the wave washer due to lack of oil.
See the line above where the "teeth" are. That line at the base of the plate where the teeth begin. That is a groove wore into the plate from the inside diameter of the wave washer. That gooey mess on the plate is from a very tiny bit of oil, that was probably from the factory soaked plates, and has since fried/baked to the plate from lack of further oiling which caused way to much heat to occur.
The line is a bit more visible in this set that was completely fried (plates included) from mis-adjustment of the cable.
That line is even more visible in this cleaned up plate. The wear is approx. 1/3rd of the thickness of the plate worn into it.
Now the above pic is the reverse side of its corresponding pic from above it. Yes, you could just flip that plate around in the stack and save some money, but unless you do the Adjustment Pin Mod (not the push pin--which is the black plastic push pin that is used throughout our bike) that wear will continue to come back again. I recommend doing the pin mod for oiling---yes, it will get some oil to your plates. I also recommend doing the 3 sides ground as opposed to the 2 side grind. Reason for that is when you grind 2 sides, if ground too much, there is a chance for side play in the pin to occur. If you grind 3 sides, you do not need to grind as much into it and the chances of side play are greatly reduced.
Just for everyone, I have taken apart atleast 30 9's for this very reason---clutch shudder. Every 9 taken apart, the clutch plates showed zero oil on them. Those bikes have run various types of oil ie: amsoil, suzuki dyno and synth, mobile 1 auto and MC, rotella, royal purple, honda, castrol 4t, and others. Our clutch is advertised to be a semi-wet clutch, but none have been wet in any form. So, the type of oil matters not, the parts speak for that. Yes, for those that just want to do the pin mod, that might work---but the damage to the #6 plate is already there and not allowing proper tension on the wave washer due to the wear (groove). So, I highly recommend you replace the parts. It should eliminate the shudder if you replace the parts and do the pin mod. One without the other, well it probably will come back at some point.
I hope this helps your understanding of what is going on inside your clutch pack and gives you a bit more info or reason to do it the right way. Any questions, well you know where I am at.
Sent from EVO bouncing off a couple satellites.