Don't understand - makes no sense

[Mattr59]

Ok, I do not understand this.

I have spark, I look at the removed plug and I see sparks. Replaced the plug anyway, in case it has a crack or something. Spray in some start fluid - nothing not one pop. Inspect the magneto, the pick up is in the correct spot. Did not check compression but from the sound of the starter, it has compression.

I was on my way home from work and the belt broke. Engine kept running, in fact, it ran well. Pulled the clutch and the variator installed the new belt. After that, it would hardly crank over. shorting the relay did not help so I ordered a new starter motor. That seemed to help, but it still cranks hard which makes no sense.

150cc Jonway

Does anyone have any ideas?