Kwattro, i dont think so. But i might be able to enlighten you a bit.
The 81 YZ465 was the first year for the beast. It was an air-cooled 2 stroke, with a 5 speed gear box, CDI ingnition, 249lb dry weight, 37.4 inch seat height, 11.8 front and 12.6 rear inches of travel, dual drum brakes, retailed for $2349 new, had a VM38mm carb, borexstroke= 85mmx82mm, and thats about it.
Super fun and fast bike. It was a buga to start unless your on TDC (top dead center) and you come up and over those bars you probably wont start it. Really good vintage motocrosser. Has amazing bottom end grunt and a huge mid to top end hit.