will a 1996 fzr engine hook straight up to a 02 r6 frameThe FRZ-600 came out in 1989.
It was heavily based on the FZR-400, which was sold in Japan and the US, though came with a frame made of less expensive steel instead of the 400's aluminum.
Because of the age of the design (the base model FZR-400 was around for a year or two), things like the funky (by 2006 standards) 18-inch rear wheel (not to mention how skinny those wheels are) help to date the bike.
The reason for the longish bore dimension again has to do with the engine, too, being based on that 400.
Only so much room was there for enlarging the bores when turning the 400 into a 600, so the stroke had to be lengthened quite a bit.
Actually, back when it was a new model, the FZR-600 was bad-ass, getting a big thumbs-up from sport riders and sport magazines, at least for a couple of years until the CBR-600F2 came out in 1991.
From there, that CBR typically got the nod while Yamaha Motor Co. sat on their FZR-600 design, only changing to a slightly wider rear wheel width (a half-inch wider, if I recall, though still skinny) and four-piston front calipers in 1990, temporarily switching to a more sleek-looking single headlamp upper cowling for 1991 and 1992 (then switching back to the original twin headlamp design in 1993), and changing the BNG (Bold, New Graphics) each year until the last year it was offered in 1999 (I think).
By then, the FZR had long been retired to the budget sporting 600 in the line-up.
The 1995 YZF-600RG was the new design that Yamaha needed to keep pace with the CBR and ZX-6R.
It had up-to-date chassis features (like bona-fide modern wheel sizes), more gnads from the engine, and fresh styling that mimicked the much more expensive YZF-750R, though the bike lacked the competition's ram air intake (big news back then).
This model stood in this basic form for just one year longer because the YZF-600R in 1997 was once again redesigned into the bike that's still sold in 2006