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Discussion Starter #1
Just seeing if someone could help me. Is it normal for these three wheelers to build pressure in the oil? To were I start opening the dip stick I starts hissing air. If not what would cause this.
 

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Four strokes do build crankcase pressure, the worse the cylinder and ring seal, the higher it goes.

Considering it’s as old as it is, and sounds like you may not be aware of its previous maintenance record and operational conditions, yours just may be having excessive pressures due to very worn components.
 

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Discussion Starter #3
Thanks bud. I'm gonna do a valve check to because I think my timming is off it's spitting gas out the carburetor. I did clean the carb to and it looked good. But I did order a new carb. But I'm sure the valves need adjusted for being as old as it is.
 

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Could just be well worn needle jet set assembly.

Those are made of brass and over time become worn to the point that they don’t effectively seal off fuel at closed throttle, thus allowing excess fuel to be drawn into the engine at idle, creating sooty fouled plugs.
Any attempt to offset this by adjusting low speed mixture screw leaner, then creates a lean condition that causes a hiccup upon throttle opening, and a “hanging” idle where they won’t return to idle properly.
 

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Discussion Starter #5
It was the carb. I put a new carb on and adjusted the valves. Changed the oil and she's running great now. I appreciate the help bud.
 

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Just for sh*ts and giggles, pull the needle out of the slide, use a magnifying glass to inspect its upper 1/3 length, and look for scratches and gouges within that region.

These wear and then rubbing against the inner bore of the needle “jet” (short insert) and leaves wear pattern resembling as if someone had taken a rat tail file and started to file on just the one location (leaving the inserts bore out of round)
Very common. Worse if air filter is poorly oiled or missing.
 

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Discussion Starter #7
I'll have to check that out and Yea the air filter box was gone off of it. So when I bought the new carb I got a pod filter to. And one more question just to make sure I got the valve clearance right. Are the valves sapost to be 0.5mm on both exhaust and intake?
 

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Here in Michigan, it requires taking to the local Secretary of State office, a written bill of sale from prior owner stating the brand, model and vin (on frames front neck tube), and the price of the sale. Signed by both, the seller and buyer.

They’re pretty ease to fudge one together if previous owner is far away or can no longer be reached.

The state you live in......? I dunno

I wouldn’t know for sure...?
 

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Discussion Starter #11
Thanks bud. And another question I have a chines 04 FLYWING dirtbike mx 150cc and can not find anything as far as parts or who made the bike.
 
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