kz750 vs kz650

Hello Hello!

I was recently forced into moving which required me to leave behind my 1979 kz650. The bike never really wanted to run like she was supposed to, but got me around stubbornly pretty consistently. However, I have an itch for a kz, and am back in the market. It seems as though my current choices are a damn fine kz750 twin, and what seems to be a mint kz650.
Being that I never got the true experience behind my 650, I am perplexed in which to buy.. or if to look for something bigger (kz1000). I am in the mountains (park city utah) and would like something reliable to tour the country, but to also scream around a corner. Any owners have pros and cons of which direction I should go?
All opinions will be appreciated! Thanks guys!

Brian, hands down my choice would be the KZ650 if for no other reason the parts support that is available. You can find whatever you need easily and at a reasonable price. I've found that you can buy a used 650 part for about a third of what you would have to pay for the same part that fits a 900 or 1000. Kawasaki made that same basic engine from 77 until I believe 2003.

If you want to hotrod it there is all sorts of goodies available to you. Also the carb spacing is the same for the KZ650/750/900/1000/1100 as well as some of the GS series Suzukis, gives you a big choice of carb options.

None of the above applies to the KZ750 twin. There is little to no aftermarket parts support, valve shims are tough to find and the starter clutches are known to be very weak. Since needed things like tires, cables, batteries etc. cost the same and in light of the fact that the twins never seem to fetch much money you would be better off putting the money in a 650 where you actually stand a chance of getting your money back.

Last but not least the 650 being a 4 cylinder runs smoother, has more HP and IMO is just a much more fun bike to ride. I know there are some people here that love their 750 twins but that's my take on the subject.

Not having owned a 750 twin, or any twin for that matter, I'll rely on Andy's advice for the comparison. I will say that a well running KZ650 is a durned fine motorcycle. The powerband is smooth without any surprises from off idle to redline. They run almost like an electric motor--just twist the throttle and go!

Perhaps my experience is enhanced by use of the Dyna S electronic ignition, ACCEL coils and wires, and the Wired George coil power mod which makes starting easy and idle smooth as silk. I also kept my gas treated with Seafoam all winter and took my 650 out for a ride on Saturday with five month (at least!) old gas in the tank and it started on the third kick (weak battery) and ran great.

All that said, I'd like to get my hands on a 440 twin "someday".

Same here. KZ650 is about the best middleweight ride you can get for all the reasons the guys mentioned. Just a joy to ride stock or modified. They must have sold a million of them because everywhere ya go somebody comes up with a story about theirs. And it's always good! There are fan clubs for a lot of good bikes out there but the KZ650 is huge.

Ditto the praise for the KZ650. I've owned mine since April 1977 and I still love it! Ed

I certainly love my 650 too!

+1 on the 650. I've never rode a twin that's anywhere near as much fun as my 650. I've never been on a kz750 twin though, so I can't really say about that...but the 650 is ridiculous fun from rabbit starts all the way through the top end!

The 650 four and 750 twin are very different bikes. The 650 will stomp that twin in a race. I have only had a 650 for the past year but I have had other KZ 4 cylinders, and they pretty much will all out perfom a twin. BUT the twins are really, really nice bikes. I rode a both a 650 and 750 twin an loved them both. The 750 has some grunt to it, much unlike the high reving power the 650 four makes. They are more of a classic cruiser type of motorcycle where the 650 four is what I believe to be the birth of the modern sport bike. (That subject is still open for debate though)

The KZ twins have counter rotating ballancers in the bottom of the crank case and run smooth as silk. I ride the z440 in my avatar as a daily commuter and it is a great little bike. The twins are just plain fun to ride, but if you want to have a classic KZ that hauls a$$ you would want the kz650 and an open wallet .

+1 on the open wallet. I just opened mine to get going on my 810 build up, man is it ever gonna sting.