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So I'm sure something has been covered here. New to forums in general and new here. Got it with the engine in a tote. New crank assembly and piston. Nothing wrong with old piston, he dropped it or whatever and bent one of the fins. So I got it to fire tonight, hooray! Can't get a neutral light, and it only stays runs with the choke out and clutch in. If I push the choke back in, dies, let the clutch out, dies. No chain on it. It's like a sensor is cutting it off with the clutch. not too sure about the choke issue. We have a big family trip planned in two weeks and I need it figured out by then. Thanks in advance.
 

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Advance the idle a bit.

Make sure tps is in spec and didn’t get bumped.
 

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So I'm sure something has been covered here. New to forums in general and new here. Got it with the engine in a tote. New crank assembly and piston. Nothing wrong with old piston, he dropped it or whatever and bent one of the fins. So I got it to fire tonight, hooray! Can't get a neutral light, and it only stays runs with the choke out and clutch in. If I push the choke back in, dies, let the clutch out, dies. No chain on it. It's like a sensor is cutting it off with the clutch. not too sure about the choke issue. We have a big family trip planned in two weeks and I need it figured out by then. Thanks in advance.
Welcome to the Forum...!

Did you put the new piston in or the previous owner did...???

Low compression can cause your symptoms...
You'll need to check the compression to make sure it's installed properly & the head gasket is sealed...!! 49~81 psi range...warm engine, throttle wide open 65~75 psi standard...!

Double check the valve clearance...?

Valve Clearance: between cam and valve lifter
Standard:
Exhaust 0.17 ∼ 0.22 mm (0.0067 ∼ 0.0087 in.)
Inlet 0.10 ∼ 0.15 mm (0.0039 ∼ 0.0059 in.)
If the valve clearance is not within the specified range,
adjust it.

Also make sure the decompression spring is on the exhaust cam...see picture below

And the cam chain tensioner has been installed correctly...see picture below
 

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