What Size Sprocket

I Have An Occ Stingray With A 80/66cc Engine. It Now Has The Original 44t Sprocket. I Weigh 165 Lbs. I Am Still Breaking In The Engine But The Motor Seems To Be Really Cranking At 20 Mph. The Drive Wheel Is A 20" . I Am Not Interested In Going 40 Mph However Cruise At 32 Would Be Nice.
So What Would The Best Sprocket To Run?

Thanks all.
The Manic Mechanic 32T and adapter worked out great comfortable cruise @ 22mph and still climbs moderate hill very well.

Xlite,
I don't know how much you weigh or what kind of hills you have. I weigh 165 and some moderate hills. The engine does not scream at 22 mph and no problem with the hills. However there are times that I would like a even lower tooth sprocket. However I would lose some hill climbing ability. the sprocket with the adapter was $48 plus shipping.(actually very reasonable for the Hi quality of the product). You can purchase the sprocket only, but it is not setup for the 9 bolt rag mount. They would probably set it up for you but I have no Idea of the turn around time.
To make a long story short, I would favor a 32 over a 36 anyday. I have put a five speed setup on my second s-OCC. I have ordered another engine for it. My only worry is putting that much load on a standard bicycle chain.