Replacing valve cover gasket on 78 CB750F

[Rockwork]

How possible is it to successfully lift the valve cover and replace the valve cover gasket with the engine still in place?

Evidently there's enough clearance to slip the new gasket over the valve cover and put it in place. I've seen it done on a SOHC, but the gasket being replaced was recent so that it had not yet had a chance to thoroughly adhere to either surface. I'll assume mine's never been replaced.

With the engine still on the bike, will I be able to clean off the old gasket residue enough to get a good seal with the new gasket?

Any cautions or suggestions?

[TOOLS1]

Unless the two frame tubes that run over the top of the engine have been removed, or modified to make them removable, you must remove the engine to change the valve cover gasket. There is no way to do it with out being able to remove the valve cover from the engine. I would also recommend replacing the rubber nickles that are located under the cam towers that seal the holes for the head bolts since you have the engine out of the frame.
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[Lincoln Highway Bullitt]

I have a 1980 cb750f and had the valve cover off twice now. The last time was for new gasket. I didn't have any problems. No frame mods or engine removal either.

[Rockwork]

Thank you, but my understanding is there is not enough clearance up through the 78 SOHC. There's only about 2-3" clearance between the valve cover and the frame, which I was wondering whether that was enough to clean the old gasket off and slip the new one on over the cover. I've seen it done, but not sure I can clean off the old gasket well enough with that little space.

[TOOLS1]

1980 is a DOHC engine, totally different engine/frame.
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