I didn't know who manufacture arrow engine.
since but the others seems to follow arrows trend over the carb selection.
the arrow carb have good consistency.
I ran over 5 months and no hiccup.
try the speed crank, didn't like it.
since gone back what it is. I could forsake a little low end, compensated by smoothness.
but the high end, is a monster.
I like the arrow simply becos it is a simple 3 ports engine with blazing long straight speed.