F6B engine knocking noise when braking/pushing on suspension?

[rdbonds]

Very interesting. As I recall, there are no points on the engine where any rotating assembly extends outside the engine (i.e. no pulleys, harmonic balancers, etc). Just to be sure, I found this ebay listing that has nice photos of a GL1800 engine (which also happens to be from an F6b).

https://www.ebay.com/i/254364995116?...saAvNyEALw_wcB

The engine in these bikes is a stressed member (i.e. the frame bolts to it...it's structural). Has the bike has suffered an impact or wreck?

[dashiznit1]

Very interesting. As I recall, there are no points on the engine where any rotating assembly extends outside the engine (i.e. no pulleys, harmonic balancers, etc). Just to be sure, I found this ebay listing that has nice photos of a GL1800 engine (which also happens to be from an F6b).

https://www.ebay.com/i/254364995116?...saAvNyEALw_wcB

The engine in these bikes is a stressed member (i.e. the frame bolts to it...it's structural). Has the bike has suffered an impact or wreck?

As far as I know and can tell it's never been wrecked. I'm completely stumped.