vm40 mikuni carbs info - Snowmobile Forum: Your #1 Snowmobile Forum
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post #1 of 3 (permalink) Old 02-10-2013, 09:25 PM Thread Starter
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vm40 mikuni carbs info

Hey all, i'm new to the site and need some help setting up an older engine. It's a complete rebuild 91 617cc with vm 40 mikuni carbs, my question is what should the jets and needle/seat's, as well as needle valves and valve needles be?. I currently have 2.0 needle and seats, 35 pilot jets, 420 main jet on clutch side and 440 on mag side (it helps to distribute the heat more evenly) i cant see the digit's on the valve needle or needle valve, and im thinking its the issue to my 1/4 throttle bogging issue. I've installed new needle and seats and done a complete soak and clean on the carbs, and it still does it. Can any one verify the right jet and needle set up for this particular engine and carbs so i can be sure its correct?...and any suggestion as to my 1/4 throttle bogging issue would be great full as well...thanks all in advance.
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post #2 of 3 (permalink) Old 02-10-2013, 10:25 PM
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air/fuel screws 1/2 turn IN (richer) ,see if it helps...make sure idles not too rich.
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post #3 of 3 (permalink) Old 02-11-2013, 04:42 AM
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www.hlsm.com will give you all the carb specs.

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