#42.5 idle jets

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tvmax

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I know US models use 37.5 idle jets. Some carbs have 42.5's. I think these use 100 air jets vs 90's also. Why is this? Does this slightly recurve the idle transfer to secondary or does it end up equaling the same curve thru different jets?
I know when tuning holly type carbs if you are so far out on the idle mixture screws you need to increase idle fuel jet to stop a hesitation on throttle tip in. Is this the same for the vmax carbs?

Thanks
Jim
 
I changed my idle jets to 42.5's. I also changed my PAJ1 to 95. This is the configuration for some other country's Vmaxes.

My PAJ2 is now at the stock 170's. I did the changes for the reason that, to get rid of the low rpm 'pop' out of the carbs, I had my idle screws turned out pretty far. Now they're turned out only 2 turns and the bike runs crisp as hell.

I think the higher volume lets you keep the screws in further, and let's the idle circuit help more higher up the rpm range.

I'd like to hear other guy's opinions of this.

Vinnie
 

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