Laverda Jota with the 180 degree crank. Best sounding production bike ever IMO - race tuned 1000cc triple with unsilenced megaphones. Back in '76 it was the first production bike to top 140mph with handling & brakes to match the speed :crazyloco
I believe the V-twin in Honda's RC-51 does it for me also.
A local dealer in town had a new 2005 RC-51 on the show room with 75 miles on it.List was $10,700.Looked sweet,but I needed to add the ZX10/lime Green to my resume.