AMA Vintage V5 rules on 1986 VF500F

This isn't really an important question, but something I've always been curious about. Is there something about the 1986 VF500F that gave it a racing advantage or potentially made it unsafe compared to the 1984-1985 versions? If I'm not mistaken it actually had a lower outright HP number due to the carburetor/inlet differences.

I'm wondering if this rule was specifically to try to keep all bikes 1985 and older in this class as there are a lot of "pre-1986" statements. It's probably that. And then the EX500 just got an exemption because there were so many of them and the bike was effectively unchanged until like 1992.

I always just found it kind of funny it singles out one year of the VF500F (probably just coincidently) while grouping them with the TZ750.

 

I think they are just ill-informed or just not bothering to clarify. They were just keeping out the 86 VFR 750/700s and lumped the 500 in there by mistake.

The 86 500 has no real racing advantage except for maybe more reliable.

 

Ah, got it--thank you Captain. Funny I managed to forget about the VFR's introduction on the VFR board.

 

The 84 engine in my race bike def felt more powerful and faster, but I set my fastest lap time with the 86 engine.

I think the 84 firing order with my exhaust just felt and sounded more "raw" and by the time I swapped in the 86 I was just more used to the bike and track.