How level does the engine need to be?

Fletch

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I have my engine mounted at almost this exact same angle. I have the Z extended intake though which is longer and puts the carb at a slightly higher angle. I was thinking about adjusting the mounting to make it more level, but if it isn't necessary I'll leave it alone. I have only ran the bike for a couple minutes so far before the chain tensioner went into the wheel.
 

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Get the carb bowl as level as you can. Anything else is of no concern. Is the rear mount perfectly flush with the seat tube? Pictures below show correct mounting fit on the rear mount.

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Get the carb bowl as level as you can. Anything else is of no concern. Is the rear mount perfectly flush with the seat tube? Pictures below show correct mounting fit on the rear mount.

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The rear mount is perfectly flush. Unfortunately there's no way I can think of to level the carb without moving the whole engine. I want to get a billet intake down the road which would solve that problem. Hopefully it will work out fin for now.
 
At this time there is no need to worry about the angle of the carb. I have seen worse and still run fine. I feel that at the angle yours is in that there is more then enough fuel in the bowl so that it isn't being depleted too fast for refill. If when you get running down the road, and more fuel is burned with the increase of RPM's that will be the test.
 
Since your carb isnot quite level, a needle valve adjustment may compensate for it. Search the site for "needle" and see if you get some posts explaining that adjustment.
 
I don't think the needle adjustment will have any effect as far as engine angle . What the problem might be is that at a angle the float is not level. The higher the rear of the engine is the more fuel can enter the bowl. The lower, the less fuel can enter. What you might need to do down the road is adjust the float setting.
 
I don't think the needle adjustment will have any effect as far as engine angle . What the problem might be is that at a angle the float is not level. The higher the rear of the engine is the more fuel can enter the bowl. The lower, the less fuel can enter. What you might need to do down the road is adjust the float setting.

AlFisherman,

I have the cns "racing carb with all the jets and blue air filter. I took it apart and didn't really see any adjustment on the float. I'll have to double check that if it becomes a problem. Thanks
 
AlFisherman,

I have the cns "racing carb with all the jets and blue air filter. I took it apart and didn't really see any adjustment on the float. I'll have to double check that if it becomes a problem. Thanks

If a carb has a float then there is a adjustment. At least that is what I've found on every float carb. There is or should be a tab that pushes up on the needle into the seat as the float rises and drops the needle off the seat when the float drops (as in running out of fuel). Adjustment is accomplished by bending the tab.
 
Hi, im sure, as long as the carby is level you can run this 2 stroke engine upside down. The angle does look high in the picture. But when you consider all the angles it goes through in normal use. i cant see it hurting too too much. Fuel surge/starvation perhaps? A set of longer forks would solve it somewhat. Can you lower the front axle a little or drop the back? you may pick up 1/2 a deg at the float level here and there. your float should be 1mm below the top of your main jet when upside down. But, because its tilted it may now be 3-5mm out.

Phillip
 
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