Uneven exhaust pressures

Hi all,
Can anyone help with this, I've just rebuilt the engine with new pistons and valve seats recut,
Since the rebuild I've cleaned the carbs twice, it was running too lean straight after the rebuild and now on the rich side. I've got the mixture screws between 3 to 3.5 turns out. I've attached a YouTube link so you can see I've balanced the carbs the best I can but one thing I've noticed that the left side exhaust has a lot more pressure and sound than the right side.
Any ideas

Cheers Pete.
Just incase the link doesn't open, its in
YouTube kz1300 uneven exhaust pressures

Did you check the compression figures?

Also, are those "old" mufflers? Is it possible one has less baffling than the other?

I hope the compression isn't low or uneven after an engine rebuild, but will have to check that later. The exhaust cans are only a couple of years old so they should be ok.

You got a lot of new parts and new surfaces to be matched going on there and its early days.

I would be doing at least 1000 miles before worrying too much.

How do you know the left side exhaust has "much more pressure" ?

Pete F
Uk

Hi Pete,
Just did a compression test, all showing around 150 psi, so that's a relief.
I don't know if you watched the video, but you can feel and hear the difference, left side has a lot more noise and pressure compared to the right side.

With good compression on all cylinders I'm pretty sure your issue isn't valve adjustment. Sorry to say it but I think your issue is with the carbs.
When you start it up from cold which pipes get hot first?
Bill