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Jetting - Big Bore CRF150RB - minor tuning questions

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Question for the experts ...

Just had my wife's CRF150RB converted into Big Bore 162 CC engine with a slightly higher comp piston.

The bike already has TONS of mods on it, and airflow is phenominal (thanks to an MRD exhaust).

2 things that I am still trying to "fine tune" and would appreciate any input.

Jetting before Big Bore Kit:

PJ: 45

Main: 142

No bogging at all ... runs like a champ.

Now I did not change the jetting at all ... yet ... and after the big bore install the bike runs AMAZING, but has an annoying hanging idle. No bogging, just an erratic idle and immediate stall upon pulling choke. At full throttle down the straights, a bit of popping can be heard during acceleration (not when the throttle is let off).

Now could it be possible that a leaner PJ is needed (ie 42) BUT a larger MJ is required (ie 145) ???? Does this have much logic to it?

When the bike is running, anytime the choke is pulled, it stalls immediately.

So in essence, what I am trying to tune is a slight hanging idle and a bit of popping at WOT applications during acceleration down straightaways.

Seems strange to be downsizing one (PJ)and upsizing the other (MJ) but based on the symptoms, does this seem even remotely plausible?

Any input would be appreciated.:worthy:

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Hanging idle is caused by a lean condition, so you want to go up on the PJ size. Cant help with the popping on accel.

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