I dunno about this, but I'll give some comments. I do believe an 86 is faster, since it has the 6 speed tranny. My Z only goes 55 tops right now, but I'm running 12/44 gears with 22 inchers. I plan to put a front sprocket up to 14, so I should be able to go 65 after that, I also want to put a 42 rear sprocket on, I'm not real concerned about accelaration, I want top speed because most of my riding area is always 50+ mph. R's and Tecates are both more powerful and faster. The Tri-Z is like the crappiest of the 3, but still not a bad machine in my opinion. If I remember correctly I think an 86 or 85 R came stock going 85 mph, that's pretty damn fast.
Trikes:
1973 Honda ATC70-orange!
(2)1985 ATC70
1985 Big Red 250
1985 250R