WaveEater Powervalve Clip Kits
The older style OEM Yamaha power valves used on all Yamaha GP800R, GP1200R, XLL1200 and XLT1200 up to mid 2001 had two problems.
The first issue was there were no solid stops to keep the valve from dropping into the piston. This problem is more common than people think. The only way to tell if this has happened is to remove the covers and measure how far the valve drops down when fully closed. To measure place a straight edge across the cover surface and measure down to the top of the stem. If this measurement is over .43" (11mm) then the stops have worn and allowed the valve to rub the piston. You can still install the WaveEater Clips to keep further damage from happening but realize that for every fraction of an inch you measure over .43" means that the bottom of the valve has been eaten by the piston that amount.
The second issue, as with all versions of the Yamaha powervalve, the pin slides out. The sides on the WaveEater Clips retain the pin in place for worry free operation.