CBR600 F3. Amazing bike, but the motor buzz killed it for me. I never felt the bike disappear like my Hawk GT would.
91 VFR: Almost the opposite of the CBR. LOVED the motor, but felt like I was trying to straddle a hippo and I could never figure out what the front end was going to do. Ironically, the 98 VFR I bought years later was divine (best motor sound ever), but I sold it because the roads are really crap around here, and I was going to end up with way too many speeding tickets on the freeway, it was just loping along at 90.
KTM 990ADV. Test rode my boss's bike, after lusting after it for years. Whoa. The ergos were wrong, the controls (except the clutch) seemed wooden, and the motor was less exciting then my XR. It felt like sitting on top of a beautifully chiseled wedge of granite. Pretty, solid, and oddly cold.
The bike I expected to dislike but loved? 89 Transalp. For such an...interesting styling exercise, that bike just connected with me and I haven't found anything else that comes close to that yet.