Quickie: KZ550 vs KZ440

I have an 83 KZ550 and love it so much that my gf wanted a bike and we found her an 82 KZ440 from a local shop. They had replaced all the fluids and [I think] did a tune-up so it was all ready for the season.

The KZ440 runs just fine, and my question is how there is such a jump in performance from the 440 to a 550.

My 550 has no problem doing 85mph while two-up (total 330lbs of riders) but the 440 barely holds 60~65mph while on a flat highway. My 550 has four cylinders and the 440 has two... does more cylinders translate to more torque and thus the difference in performance?

Thanks for any helps understanding! I dont think anything is wrong with the 440, but I suppose it could be...

Thanks all,
Dustin

That 550 has the benefit of maybe 50-55 horsepower. The 440 has about 35-40.

Hey D...
If you had one size bike, say a 500cc and each had a different "drive system" ie: shaft, belt and chain I imagine a person could tell the difference based on torque, acceleration and shifting.
Also, "There is no replacement for displacement"
Sometimes riders will adjust their top cruising speed and/or acceleration and associated rpm by swapping the front or rear sprockets (for sprockets with different numbers of teeth) on a chain drive machine. It gets trickier with shaft and belt drive. :blink:
The KZ440 (gods strike me down :laugh:) is not really designed for extended highway cruising and some would argue the 550's not either. The Kawa engineers had other plans on the drawing board for those tasks.
Nice that Sarah got a bike too...enjoy the riding and stop by anytime.

Post edited by: neilage66, at: 2007/05/07 21:44

My old KZ400 did 100, but barely. If you can't do 75 on the 440, there is something wrong.

I think with a "light" rider the 440 should be able to easily maintain highway speed. I'd say there is probably something wrong. More cylnders will = more torque, and theres no substitute for HP but still... If it is running good everywhere else it is probably something simple. Check out the plugs, air filter, points if you have them, fuel filter, all the basic stuff. Whatever you do, if you ever take those carbs apart, treat those rubber parts on the slides like gold!

more displacement and more pistons = more power. however twins usually have more torque than a 4 cylinder of the same displacement if compression ect. is the same, but the 4 will make more power because you can rev it more. if you had 2 550s and everything was the same except 1 had 2 pistons, and the other had 4, the twin would have better "grunt" while the 4 would have more top end

eMusicMan wrote:

... the 440 barely holds 60~65mph while on a flat highway....

Just guessing -- maybe the timing advancer is stuck?

Hey thanks everyone for the feedback! This weekend I plan on sitting with the bike and going through it step-by-step to see if I can at least figure out where the problem might be.

At least three people now have mentioned the ignition timer - I'll be checking that as well. Thank goodness for the good ole Kawa Service Manuals!

Regardless, I'll post-back here with what happens...

Cheers,
Dustin

yup definately something wrong, my old honda night hawk 450 could hold 120-130 km/hr all day.

I have an 82 440 LTD with the belt drive. I weigh about 170 and I have no problems with sustained highway speeds. I would definitely agree with the others saying that you have a problem somewhere. Just my $0.02

Hey all - I nearly forgot to post a follow-up to this. Come to find out that yes something was a bit 'wrong'... as we had pretty much determined.

I simply started running some Sea Foam through the gas and put it in the carbs for awhile and now each time I run it, the thing runs better than it did before. Just this past weekend I had her doing 75+ on a flat stretch of freeway!

Anyhow - just FYI!

Thanks again to everyone for the assistance...

Cheers,
Dustin H

yeah the 6 speed helps the lil' motor out. Well tuned they make about 40 hp and that is significant for a bike this small. I've been just over 90 mph and it was still pulling. My bike is not stable at that speed and develops some ugly osclillations. I am working on my forks this week and mabey with a new front tire it would get better, but 80+ is just not what this bike is made for. But at 65-70 mph it just purs along. Kawasaki put just as much design effort in thier small bikes as the rockets and cruisers, they build one hell of small engine. My 250CSR (single cylinder 4-stroke) goes, and I will swear to this, 75 mph and I am over 200 lbs. Again, that is way too fast for a bike that light with a mechanical front break.
But a testiment to lil' Kawa-kazi's everywhere.

Post edited by: Tyler, at: 2007/05/14 22:50