Topic: 1978 CB750K Engine Noise

[bagatyr]

Hey all,
My 1978 CB750 is coming out of a bit of a hibernation. It hasn't been started for several months. Now it's making this noise.
I did the full 3k tune up before i shut it down, drained the carbs, would prime the oil pump every couple of weeks so it got some oil through the engine.
I just pulled the cam chain tensioner to lube it and make sure that it was working. Are the carbs out of sync? It's almost like a small backfire, it and it happens regularly so maybe one of the carbs is blocked somewhere?

EDIT:
Ran the bike for a bit longer as it didn't sound like a metallic sound, but it had a definite rhythm. It got a bit better and is now steady at idle. Bike now stumbles when I pull on the throttle. Definitely a carb issue, will be cleaning carbs and reporting back.
Thanks everyone!

[flybox1]

if you have PD carbs, clear tube test the fuel levels in all bowls.

when was the last bench/vac sync of the carbs?

[bagatyr]

Last vacuum sync was a couple of months ago, I synced it and put it in storage. Does the clear tube test just tell me if a float is stuck?