4 stroking and too lean???

borntofli said:

Is this possible.... The plug is grey-tan but the bike 4 strokes bad....

It runs worse if I move the needle richer, so I must need a smaller main jet to get it runnin right....

Stock is 70?? so i would need to get a 72?? or a 68 to get leaner????

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Are you doing a plug chop to identify the condition?

I don't want to comment on your tuning as I'm not an expert in the area. I don't want to feel responsible for a blown motor.

However, the jet size depends in how you are looking at it. Are wou looking at wire gage, or mm? A numerically smaller wire gage size is actually a larger hole. Obviously, a smaller mm size jet will have a smaller hole. To go richer, you need a larger hole, so either a smaller gage size, or a larger mm size. It's kinda confusing, so watch how the jets are labeled.

borntofli said:

It 4 strokes at all throttle positions....I ran it down the road at cruising speed and shut it off when I hit my driveway....Its a new plug so it doesnt have any color on the ceramic part....

Is a 68 leaner than a 70, or is a 72 leaner than a 70???????

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I need to apologize. I talked about wire gage before. I was wrong. It's actually drill #. Same difference though.

I can't answer that unless I know if you are talking about drill # size or diameter in mm. The two different units go in opposite directions.

If it's drill size, 72 will be the lean one.
if you're talking mm diameter, 68 will be the lean one.

Where did you get the jets that you have? Some vendors list the units that they measure.

i would lean towards an air leak.carb gasket or carb mount on pipe.
check the cap that screws on top as well.
if raising needle didnt help and lowering it didnt help,the next course of action would be choking it while driving to see if it worsens.then something i tried was to close the tank valve and drive it til it runs out of gas.mine smoothed out and started to pull,i opened valve a little to keep gas coming in,but its impossible to regulate it.
lowering float adjustment may also lean it out a minute amount,as it takes a little more to lift the fuel.
i bought a set of small number drills,and soldered the jet closed and redrilled it two sizes smaller.im at #76,think i could go smaller.

Do you have an NT carb or ?

NT jets measured in mm
Sizes range from 0.60 to 0.84 mm. Stock size is 0.70 mm

http://www.sickbikeparts.com/catalo...ucts_id=116&osCsid=p7pvfe05stp8menl6cj9fsuim1

borntofli said:

Sounds like i need to try the spray carb cleaner around the carb while its running to see if it has an air leak.....

I just went to the store w/ it and had to lay it over to keep from going over a car..... I went under it, good thing he stopped in time..... Only bent 1 peddle and the chain guard.....

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Glad you're safe! Car driving people are jerks. Says the guy who just got out of his car...