02-11-2020, 08:50 PM
(This post was last modified: 02-11-2020, 10:16 PM by Bob Culver.)
I am not familair with the Big 7 but on other makes a loose front pulley gives these symptoms. (In a small Seven a loose flywheel!) Accepted "'modern"' (post 1930s) practice is that no bearing should rub, and certainly not shells, but with white metal often OK..