Keihin idle circuit + main jet

How much does the main jet affect the idle circuit on the 12mm Keihin found on PA50iis?

I have a bike with a newly built Stocko Shocko 60cc and Proma Circuit with a 12mm Keihin. This bike ran well with the stock PA50ii cylinder + Proma with a 78 jet. I upjetted initially to an 82 and felt like this would be a good starting point to tune from. The bike rips in the powerband (like I accidentally wheelied it) but as is often the case with these carbs, has trouble idling.

I know common wisdom suggests the idle circuit is clogged, but I assure you it isn't. I've soaked this carb, blown it out with compressed air, and ran guitar string through all the holes.

It does seem to actually idle okay when first started up, so I'm leaning toward it being rich on the idle. So I'm wondering if upjetting has any effect on this circuit, since it does pull through the jet, into the atomizer hole, and through the idle circuit.

Re: Keihin idle circuit + main jet

Did you pull the Welch plug and clean behind it?

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