05-06 ZX6R Vibration past 6k killing my hands - reed valve
Just posting what I found.
Past about 6k I would get a wicked vibration in my handle bars. It was so bad that it would cause my hand to go numb. Imagine holding onto a dremel set at max. That's how bad it was.
It turns out it was the reed valves for the clean air system on the bike.
For whatever reason they would vibrate out of control. After I removed them the vibration went away. I got the block off plates and just unscrewed the reeds so that I could put the blocks back on the valve cover so it would still seal.
My guess is that over time they wear out and lose their stiffness, or because I removed the exhaust valve and put a slipon on which reduced back pressure in the exhaust. I have no idea for sure, just that it is the reed valves.
It seems to also be linked to miles on the engine because my buddies bike is the exact same as mine, 06 zx6r with no exhaust valve and the same slip on, and he doesn't get it. He has 9k miles and I have 30k. I've done all the maintenance too, shimming the valves, replacing all rubber, throttle body balance, everything. My bike has also never been crashed in anyway.
The only clean air system is used to pull air from the air box into the exhaust to help fuel the catalytic converter. Getting rid of it will only make the cat less efficient.
So if you are getting this vibration, get the block off plates and remove the reeds from the rubber blocks.