Seized motor.

[maybe73]

I just bought a 1977 cb 750f for $300. Has seized motor from setting for "a bunch of years". Was told it ran when parked. Bike is complete with correct title. I went to owners house to just buy the tank, came home with whole bike. Now, I hear all different miracle concoctions on liquids to put in cylinders, heads. crankcase, transmissions and how to do it. Any one with real success that can help with what they used? Any suggestion on liquid formula they used, would be a great help. Thanks again.

[Re-run]

Marvel mystery oil mixed with some penetrating oil.

Take out the plugs and put in a probably a teaspoon or so, maybe 2, and let it soak a few days.
Put the bike in 5th and start rolling it with the clutch pulled and then pop it.

I would try pushing it in 5th first in case it isn't locked. If the motor is locked, that means it will need to come out even if you break it free. The sleeves will need to be honed at a minimum, most likely bored out some and new pistons of course.