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Discussion Starter · #1 ·
Hi all, i am attempting to adjust the carbs on an '86 Formula Plus. I have read thru the manual and other forums but cannot seem to get it corrected. The slides were a 1/4 to 3/8 inch from clearing the carb throat. Once i set the slides to clear the throat at full throttle they do not return far enough down to touch the idle adjustment screw. When the slides are far enough down to touch the screw they don't go all the way up. It idled correctly last winter so i know they are sitting way too high now. I pulled the engine to do some other repairs so i cant run it now, but i would like to get them close as possible before they go back on. Any suggestions?
 

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Hi all, i am attempting to adjust the carbs on an '86 Formula Plus. I have read thru the manual and other forums but cannot seem to get it corrected. The slides were a 1/4 to 3/8 inch from clearing the carb throat. Once i set the slides to clear the throat at full throttle they do not return far enough down to touch the idle adjustment screw. When the slides are far enough down to touch the screw they don't go all the way up. It idled correctly last winter so i know they are sitting way too high now. I pulled the engine to do some other repairs so i cant run it now, but i would like to get them close as possible before they go back on. Any suggestions?
Sounds like you have the wrong cable or throttle lever!
 

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Chances are you have the wrong throttle flipper. The majority of people changed the factory throttle block & flipper for a progressive (dual stage). Set your carbs up to idle and see if the slides on the bell side (airbox)comes flush with the top of the throttle bore. If yes then you won't see any difference in top RPM / speed. Most people stress on the engine side of the throttle slide being flush to the throttle bore but the difference is only a few CFM if the engine can reach that RPM.
 

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Discussion Starter · #4 ·
I had to change the broken throttle lever on it and the wiring for the heater was different, so maybe have to get the correct lever. Will have to ck and see what was stock as far as cables. so hard to find info on the parts for these older sleds. Any sites u guys use that has parts drawings and numbers?
 

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VM 40's had a longer throw than anything else in the day, chances are that you do have the Wrong Cable.

1982 9500, or 1989 Plus, had VM 36's with oil injection, and VM 36's don't have the travel needed for the VM 40's
 

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For sure wrong cable/lever.
 
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