[mark]

Try unblocking the air corrector holes, they were open on my cvh build with zx6r carbs and that ran fine with a rejet, it was well within emmisions limits for iva

They are also open on spuds zetec which also runs perfectly with bigger jets being the only modification

The only point I needed to block them is when I put the carbs on my st engine, it was running very lean on the rollers even with huge jets so I blocked them up and this richened everything up substantially, even at low throttle openings

Blocking them up made an extra 50bhp instantly so they seem have quite an effect on the mixture

It seems that with zx9 carbs blocking the air correctors is standard practice but is less common with the zx6 carbs and only done if required