I've owned 12 of these bikes and roadraced them for 5 years while I was a Honda mechanic in the late 70's
In its day they were as reliable as anything made, and even today they are very smooth running engines. Today however, every bearing, gasket and seal is 30 years old now and best left to a real enthusiast who loves to tinker. Assume you will have to rebuild the carbs and probably replace the ignition coils soon. The head gasket o-rings are most certainly weeping oil by now.
They also had points, non o-ring chains, old technology suspension and many other reasons why it will need more TLC than a newer bike. Leave it to the classic bike lovers and get an SV, or if you like Honda, get an NT650 Hawk which is like the SV.
Both of these bikes have very long life engines, better handling and you can still find parts for them at your local dealer.
Old CB's are cool because they are easy fix it your self bikes if you have any mechanical ability and parts are everywhere. The SV will probably be more reliable overall but cost more to maintain because parts cost bit more. Pick based on your desire or ability to maintain the bike yourself.
The SV is the obvious choice, better suspension, brakes, tires, ignition, carburation, frame materials and design... how far do you want to go? The CB was a cool bike in it's day but unless you want a project I'd stay away and get as new as you can. I'll probably be getting one myself within a year or two for my daughters. That or an EX 500 Kawasaki or a GS 500 Suzuki, both of which are excellent first bikes.
Dude the CB is almost 30 years old ... Leave if for the GPTB. Hey think about a car that is 30 years and has been driven 100,000 miles and then parked for 10-15 years.. Get a used bike that is 2-4 years old. SV650, GS500 Ex500... etc....
Take it from someone who worked on bikes in the 70's. They are a lot better now! Even if you could get the suspension components to be up to modern standards, the frames flex, fork tube diameters are small, the tires alone put these two motorcycles in a completely different capabilities. You would just end up getting hurt trying to keep up. If you are just putting around it might be ok but don't try and do too much serious stuff on it.
Buy the SV and ride the snot out of it. Take it from someone who owns MANY 30+ year old jap bikes. They may be fun to ride to the supermarket every now and then, but that's about it. Racing them's another matter, 'cause if they blow up it's just a short push back to the pits, instead of spending the night sleeping under it somewhere near Ojai.
Remember, you're dealing with old stuff whirring and clanking around in there, and like the previous post said, oil leaks and other horrible things (like cam chains trying to saw motors in half, etc.) are just waiting to happen.
But if you like stuff like that, go ahead and get the CB. I've got one for sale if you're interested...comes with lots of spare parts.
But whatever you do, don't get a 350 four. Even if someone gives it to you for free. You have been warned.
I have a CB650 that is 26yrs old and while i love it some of the other comments are true. It's a blast to ride but i spend alot of time working to keep it running well. It doesn't take any rocket science, i'm not terribly mechanically inclined.
But for the price, it can be loads of fun and mechanical education.
I was saving up to buy a new KLR too. I haven't ridden a bike in 13 years. Finally I realized that with my gap in riding, I am better off with a used cheap bike for a season or two. So, I just got a 1982 Honda CB450T Hawk for $500. If you have more recent riding experience then this may not apply to you.
I agree with most of the above posts with just one small addendum: why not buy both?
The CB, as pictured, is way overpriced. The rusted chain itself along with the half-flat rear tire should set off a very loud alarm. No front fender, a grooved front brake rotor, missing rear components - all indicate the status of this bike: a 30 year old beater.
IF it runs, offer the current owner maybe $150 and be willing to "negotiate" another 25 or 50 to make him feel good about the deal. Then be prepared to spend at least another $600 or more on missing parts, cables, brake components, chain, tires, tubes, valve stems and whatever else you later discover. Then you'll have ... yep, a thirty year old motorcycle. You might also factor in the cost of a cell phone and roadside insurance depending on your risk tolerance.
Buy a used SV (or something similar) too. Around here you're looking at $3 k or so that will get you much newer technology and if you find a good one, it will be pretty much ready to ride.
$4,000 will get you two bikes. Treat them both with kindness and care and you'll be rewarded with two different rides for your efforts.
P.S. Under no circumstances should you extend this analogy to members of the fairer sex.
Couldn't agree more on the comments about the old CB. Mine runs great, the previous owner actually rode it 35 miles on the highway to deliver it to me. But I still need to spend about $500 on tune up, carb cleaning, new chain and sprockets. And probably another $300 for new tires etc.
All the other negatives posted here are likely right - this bike has been neglected! Here's another issue: Bikes with one front disk relied on the factory fender brace to keep the forks from twisting during hard stops - but his fender and brace are missing. At best, you'll find you have to steer it straight under hard stops - at worst, a fork might bind. Count on having to find a fork brace.
I've owned both...even if the CB550 just rolled off the assembly line, the SV650 is worlds better in performance and reliability. So the question is: Do you want to restore a nice old bike like a CB550, or do you actually want to ride places?
I went and checked out the CB and it looked like a major project to fix it up. The gas tank was rusting out and the muffles had rust holes in them, the whole bike needs work. The owner had also "miss placed the key" so he couldnt start it up for me but he said "it runs great." I took the "miss place key" as a bad sign and passed on the bike. I still like the old bikes, but I think the SV will be a better bike for now and down the road I can pick up a project bike.