1973 Z1

[Adrian90s]

Hi guys,
Been running the bike a few weeks ( weather permitting) and I can hear a low frequency rumbling at the low end of the engine (stethascope) its not always there and the bike appears to run OK.
It's had a top end refresh and the camchain is the correct length.
The cam adjuster was broken and is now replaced and I have 125 psi on all 4 cylinders. The carbs were overhauled and set up ok.
Heard horrendous stories of crank bearing failure whilst in the brass cage due to rust when stood some time....mine was.
Would a video help someone diagnose? Anything else to check...oil pump?

Thanks Guys

[Adrian90s]

Who is this man with the nickname Buzzard? Perhaps he can help with the diagnostics.
Thanks

[warren3200gt]

Dave Ennis. Buzzworks.

[gray]

have you balanced the carbs recently? I once bought a 400-4 with a horrendous bottom end rumble ( for a song) which went away when I balanced the carbs

[ADRIAN H]

sent a pm with Buzzworkz details on.

[Adrian90s]

Apparently the carbs are not balanced, I thought my motor man had done it...he though I had done.
I only have the 2 cylinder carbtune , will I have to get the 4 cylinder or is someone close to me who would volunteer/rent the correct item
Someone to watch over me is good...I only know flat twins!

[warren3200gt]

Easily done with 2 cylinder carb tune. Choose cylinder 3 as your datum. Balance 1&3, 2&3, 4&3. Then you can cross check any pairs.

[Adrian90s]

Thanks for the help guys, my engine man is going to assist me with the correct tools