Since owning one, I like them for the following reasons:
1. Cheap to buy
2. Cheap parts
3. Parts are still available from Honda (Try THAT with any other 30-year old machine)
4. Reliable as hell
5. Easy to work on
My personal tale of getting one:
I am in the Army, stationed at Fort Polk, Louisiana. It's the ass-end of the earth, let me tell you. Well we got hit pretty hard by Hurrican Rita (Katrina spared us), and we were without power for days and fuel for weeks. My daily car is a mid-sized SUV that gets decent milage (18/25), but after three weeks of no gas at gas stations and when gas DID arrive, lines were 2 and 3 miles long with fistfights and guns being pulled at the pumps, I decided I needed a more fuel efficient vehicle.
Enter the motorcycle. I decided to get one for the daily commute and to bang around town to save gas. Back in the '60s and '70s, my dad owned a few Honda 350 Twins. He never specified Twin or Four, just that he owned "Honda 350s" and they were the best bikes around. So I set out to try and find one. I knew they could be had cheap and being a 350, were probably good on gas. Plus, they were old-school, which attracted me since I feel I was born too late.
So I went on eBay and typed in "Honda 350" and a whole mess of 350 Twins popped up in various conditions. But one auction caught my eye. It said "Honda CB350 Four Cylinder - RARE!". Out of curiousity I clicked on it and saw a ratty, snotted out 350 Four. But I was intrigued, why would Honda build a Four and a Twin of the same displacement? So I typed "Honda CB350 Four" in Google and found this website.
I was a goner at that point. Seeing that Honda (widely) released the first four-cylinder road bikes and compared to the bikes of the era, they had disc brakes, electric start, didn't leak oil, started every time and were fast, well I had to have one. I started comparing the different models and first settled on a 550 after I read that the 350 was really slow, (and 350s were VERY hard to find in good all-original shape).
After seeing some pictures of the 400F with its swoopy exhaust and cafe-racing looks, and reading that it was intended for the younger, more hard-core rider, I had to get one.
Ang here I am, proud owner of a beautiful CB400F that is everything I expected (reliable, good on gas) and is fast, fun to ride and timeless. While other bikes are certainly faster, the 400 just has something about it that begs to be ridden. A personality? A playful little voice that calls to me? Absolutely.
Modern machines are soulless speed machines that tear up the pavement, but these old Hondas really have something the modern bikes don't. Personality? Soul? I'll let you decide, but I think you all alrady know since well, you're here.