24-06-17, 02:05 PM
Having done all that work on the carbs only to find that the bike still misbehaves… yes, I’m not surprised you’re having a rant!
It sounds as though one or more cylinders are not contributing. A plug check might give some information, but if you’ve not already had them out, go carefully! They may not unscrew easily from a bike that’s spent a lot of its life sat out in the weather… you definitely don’t want to shear them off.
It’s possible the fault is electrical rather than down to fuelling.
As an easy next step, I’d chuck the original plug caps and trim the leads by 8-10mm before fitting some NGK replacements if that’s not already been done.