I read the first 6 pages..... SO what is the verdict? There is a nice 450 for sale around here that is complete and cheap..
Probably the wrong forum to get an unbiased opinion on. Most people here feel like the CB450 is somehow encroaching in their territory...haha...except 754...he's got his head on straight.
My opinion is that the CB/CL450 is probably "up there" as being the
quickest vintage bike from Honda, a close second to the CB750 (not including the larger CB models). The CB450 will give the CB750 a run for it's money in short city distances (rural street driving and with better street handling), and I'm 100% sure the CL450 will best the CB750 0-60. Obviously the bigger bikes will do better for long distances with lower vibration.
They are light weight, fun to ride and handle. They were impressive back in the day when they came out, and they are still impressive to me. It's a neat package for a twin. I've only put 300 miles on mine before I tore it down, but I loved every second of it (except the part where the stock clutch cable gave out, and I had to lurch the bike 4 miles home through 10 stop lights). Favorite bike out of the three I have. Now I just need to finish my restoration...
And put those CB750 stock bars on my 'K8!
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Give it a ride and see for yourself. Bring a compression gauge with you. There is some maintenance involved with the valves. As long as you take care of the CB450, it will last while. When you start skipping oil changes, forgo adjusting the valves, then things don't work out too well. Mine had 125 PSI on both cylinders after a valve adjustment--which is a weird thing to do on these bikes--using an automotive and not a motorycle compression gauge before I decided to pull the engine. There were some other things that I wanted to correct too.
How much is this person wanting? They can be had for very cheap. I only picked mine up for a few hundred bones.