ฝัง
- เผยแพร่เมื่อ 22 พ.ค. 2021
- This as a partial install of closing and opening shims on the vertical head intake valve of a Ducati Monster S2R1000. The intent is to show a close up of the shim R&R process. This does not show how to properly check the clearance of the valve shims.
The video starts with the closing shim already installed as well as one of its two collets (keepers). At this point the cylinder is filled with rope and crank turned to compress the valve shut. The process shows taking pressure off the closing shim by pressing the closing rocker arm down with a clean breaker bar. I actually use my shoulder to press the breaker bar down so that both hands are free. The closing shim drops, second collet is installed and pressure is taken off the closing rocker to seat the closing shim. The opening shim is then installed on top of the valve and the cam is rotated to slide the opening rocker back onto its cam lobe.
Once the opening rocker is aligned, the cam is rotated, taking pressure off the opening shim and shim spun to verify its not binding. The cam should also be rotated through the valve closing phase to verify there is no additional drag or binding. If the cam is hard to rotate though the valve closing phases, one or both of the closing shims are too tall. After checks for binding are complete, valve clearance checks can take place.
Italian madness.
Nice closeup of the install. I have done this job a few times myself on my S2R800, a bit fiddly but a DIY for most competent owners. TBH, while I admire the desmodromic valve system, I think it became obsolete by about the 1980's as valve spring technology improved.
Thank you. I did this first on my S2R800 before I swapped the S2R1000 powertrain in. The procedure is identical and the shims are actually the same depending on the year. I like the Desmo valvetrain but I have to admit for a system that has no theoretical valve limit, it doesn't make a ton of sense on something with a lower redline. But then again, I don't think most buy an Italian anything because it makes perfect logical sense.