For me, the best looking bike ever is the Triumph/BSA X75 Hurricane, please note, best looking, not best bike. 2nd being the 885/955 Speed Triple in roulette green (mine is black) 3rd T160 Trident 4th = Ducati 916 and MV Agusta F4 Worst Bimota Mantra, what were they thinking?
Beauty is, as always, in the eye of the beholder and one man's view of "ugly" is almost equally and uniquely personal. I've always loved the "brutal handsomeness" of the Mk 1 Speed Triple and especially in completely standard trim. There is, for me, a wonderful design 'coherence' about them that belies their real life heft. The image below is a copy from the 'net that lets the studio setting and photo quality promote that "big boy's toy" image. Ironically, I'm a very small and very old man but I do LOVE my toys. In 'real life' they're handsome - no doubt about that - and I think a little bit of subtle 'styling' in the polished rims actually lightens the overall feeling. Fireball Orange - definitely is when out in the sun.
There are so many beautiful motorcycles that it's difficult to choose. To me, the Hayabusa is very ugly. I also find the aesthetics of a lot of cruisers very challenging.
I'm not a big fan of cruisers, but I think the Indian Scout is a really nice looking bike, a classic American cruiser. I must admit I quite liked the CCM bikes when I saw them at the Motorcycle Show last year - stripped down back to basics motorcycling..... a bit expensive, but at the time they had some pre-registered ones under £10,000 and I was almost tempted. Except I didn't have £10,000 to spend on a bike! The BMW GS's are big heavy lumps, but I got to ride one at a BMW open day a few years back, and it was fantastic. Until I had to stop and park it!!
I wouldn't call my ZZR pretty either but, with high speed "sports tourers" like these it's more about finding a balance between efficient aerodynamics and comfort. It's better looking than the Hayabusa though IMO.
The Busa shape was definitely more about function than form. Boring fact I used to do land speed racing, back when it was mainly Busa's versus ZX12R's. One of the ZX12 guys, put Busa bodywork on his ZX12 as a bit of a pisstake and called it a Kawa Bugly The idea was quite funny (to us at the time anyway) but when he ran the bike, he ended up consistently faster than with the std ZX12 bodywork (something like 5-10mph faster from memory)
The Suzuki Katanas were Marmite bikes. When they first came out, a pal fell in love with the look and mortgaged his cat to buy one. I never liked the style personally. They resurrected the look recently didn't they? So I suppose that can be beautiful or Ugly depending on your view point.
How about a Suzuki B-King, another marmite bike. I actually quite like it from some angles. I test rode one at a local dealer at the time and as you can imagine, the performance from the Hayabusa engine was arm stretching.
I had a CX 500, it wasn't the best choice I'd made, but having seen the custom in the flesh once, I would have been more than happy with one. I don't know about anybody else, but is this thread making you feel old.
I've seen some interesting cafe racer kits for the CX500 which make it look a lot better! Could be a nice project.... although at around £1100 for the kit you'd maybe have to be a CX500 fan.