150cc Cranking But No Start

[heysus]

I have a 2014 Tao Tao 150cc. I have a new battery, new starter, CDI is good, spark plug gets spark, I did a valve adjustment, gas is good, BUT it does not start.

I adjusted my valves to .004 inches. Bought a new CDI, but still the same result. The battery is a lithium Ion battery, and fully charged. New starter has not made a difference. Gas is the 91 kind.

When I put the spark plug on ground, it sparks. When I take the spark plug out of the engine, my engine cranks like it wants to start, but when the spark plug is inside, it cranks and then does a "currr" sound.

PLEASE HELP.