Left side cam cover removal

[Bevel bob]

Rubbers are to reduce oil to valve guides .

[Jordan]

Rubbers are to reduce oil to valve guides .

We're talking about the rectangular rubbers retained in the rocker covers, aren't we?
I never thought of that. You may have solved a minor Ducati mystery, thanks Bob.
Is it documented somewhere, or did clever sleuthing yield this answer?

[frankfast]

Just removed mine yesterday via the method in the photo above. No problem.

[Bevel bob]

Hi Jordan, My 250 was oiling plugs so I checked and my rubbers were missing from the covers. Guides need very little oil and cams need a lot. The cam sprays oil across the head and its deflected down away from the guides by the rubber. Modern better quality valve seals probably do the job but the designer knew what he was about so I go with his idea.I also open out the head drain features as far as possible as cold and thick oil backs up in the head.

[frankfast]

I've read that those rubbers have a V cut in them for rockers with screw type adjusters so that they don't contact the rocker. My Scrambler came with shim adjusters and the rubbers had no cut in them. I've replaced those rockers due to wear with screw type. Does that mean that I have to cut into those rubbers so that they don't contact the rocker?

[BDang]

On my 125 Sport the rectangular rubber have no V or U cut for clearing the rocker with screw/nut adjuster. The top of the rockers are relatively flat where they contact the rubber pieces. Also the rockers move very little at their rotational points.

Regards,
Brian

[Jordan]

Hi Jordan, My 250 was oiling plugs so I checked and my rubbers were missing from the covers. Guides need very little oil and cams need a lot. The cam sprays oil across the head and its deflected down away from the guides by the rubber. Modern better quality valve seals probably do the job but the designer knew what he was about so I go with his idea.I also open out the head drain features as far as possible as cold and thick oil backs up in the head.

Nice work, Bob.
Good idea about head draining too.

[BDang]

The EX valve doesn't pull in oil, and so if the EX cover has the rubber piece then its purpose must be to keep more oil for the cam and not about the EX valve, or might they didn't want problem when people swapped the IN and EX covers accidentally.