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High speed carb adjustment

mahlzeit

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Guys, hope you don't feel like I'm spamming this board, but there are so many questions...

This one is about the carburetor high speed screws. I sprang for the original service manual, which was a good investment. But if I interpret the picture correctly, the high speed screws are on the "inside" of the carb rack? Meaning the side facing the cylinders? If so, I guess there is no way of adjusting the screws without taking out the whole carb rack?
 

the MfM

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You should be able to reach them with a long screwdriver once you find them ;)

If you are adjusting the high end by reading the plugs color make sure you do a high speed run and shut the engines while at full throttle and then set your anchor. Otherwise if you idle in to the dock or mooring you won’t get an accurate read.
 

mahlzeit

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You should be able to reach them with a long screwdriver once you find them ;)

If you are adjusting the high end by reading the plugs color make sure you do a high speed run and shut the engines while at full throttle and then set your anchor. Otherwise if you idle in to the dock or mooring you won’t get an accurate read.
Cutting off the engines while going full speed? Will I not somersault over the bow if I do that?
 

the MfM

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Cutting off the engines while going full speed? Will I not somersault over the bow if I do that?
I haven’t yet! I suppose you could pull the throttles back for a moment or two. But the longer you do the lass accurate the plug color will be.
 

dabomb6608

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I've not been active lately so havent read your other threads. But I'll mention this. If you are factory setup you need to run factory settings. If running aftermarket flame arrestors then look up Oside Bill carb recipe for GP1200s (Not the GP1200R powervalve version). If you are having to adjust low or high speed well beyond factory settings on a factory motor then something is wrong.
 
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