How much Power?

I have a z500(kz550) B4/A4

I am wondering how much power these bikes are meant to have .

for example if you are doing 5k RPM in 6th(about 100kph for me) if I go to wide open throttle should it take off like a rocket or should it struggle, or somewhere in the middle?

I am just trying to gauge how much is expected of a bike that can make 52 horse power I am trying to set the standard. Of course I understand that by bike is most likely "tired" and is nothing like it was 30 years ago, But I am finding it hard to repair things and not know what it should be like.

My main focus is highway traveling, and overtaking power.

Do a compression check on the cylinders.

Last I checked it was 180psi across all 4 on the spot, that was about a month ago.

You could change sprockets.......

No, at 5k rpm the bike is not going to take off like a rocket. The Z500 makes 52 hp, but that power comes on at 9,000 rpm. When the bike was new, at 5,000 rpm it made about 27hp, so you may just be expecting too much oooomph at that low rpm. If you need more acceleration you will need to downshift to put the engine rpm up to make more power. Take a look at the chart below and I believe you will see what I mean. Ed

650Ed,
I completely agree with your point, though there is one thing that makes me suspicious of that particular chart.. The horsepower and torque lines should cross at 5250 rpm, not at 6900+.. As I understand, torque is measured, but horsepower is a calculation of torque across time, and because of the nature of the formula, torque and horsepower will always be the same at 5250rpm.

Many things can affect top gear roll-on. Has ALL the routine maintenance been carefully performed? Is there a complete intake and exhaust system in place? Too many people think that gutting the mufflers and removing the factory air filter an it's box are cheap and easy ways to increase power, when the opposite is actually true. Many owners also skip things like valve lash adjustment because they are perceived as too hard or expensive, but ignoring maintenance leads to poor performance.

TexasKZ wrote: 650Ed,
I completely agree with your point, though there is one thing that makes me suspicious of that particular chart.. The horsepower and torque lines should cross at 5250 rpm, not at 6900+.. As I understand, torque is measured, but horsepower is a calculation of torque across time, and because of the nature of the formula, torque and horsepower will always be the same at 5250rpm.

The charts is from the Kawasaki Service Manual. Because it does not use separate scale lines for the torque scale, it doesn't maintain a relationship between the hp and torque curves. In other words the torque and hp portions of the graph are both accurate, but they should be viewed as two separate graphs rather than being compared to each other within the same chart. I looked at several other performance graphs for different KZ models, and Kawasaki used the same approach in those. As a result, the torque and hp lines cross at various different places depending on the scale of the chart. If Kawasaki had used separate horizontal lines for the torque scale, they could have established a relationship between the torque and hp curves which would have made the charts a bit easier to use. Ed

Charts aside, a 550 and all the K-fours large and small like to be revved. There is no advantage to taking it easy on a KZ. They are bulletproof when maintained and capable of many many years of high revving without problems or rebuild. If you don't get into the 5-9k rpm range you simply have not ridden your bike as the manufacturer intended. Also it's a blast!!! :laugh: R

Too bad that speedo only goes to 80. :sick: By the look of it the top speed is around 120 at red line.
Steve

I have the dumb 85 speedo on the 550 I have. It is strange to see the speedo react as fast as the tach. When you hammer it they scale up in unison. 1st gear stretches well past half the speedometer dial :evil:

R

TexasKZ wrote: 650Ed,
I completely agree with your point, though there is one thing that makes me suspicious of that particular chart.. The horsepower and torque lines should cross at 5250 rpm, not at 6900+.. As I understand, torque is measured, but horsepower is a calculation of torque across time, and because of the nature of the formula, torque and horsepower will always be the same at 5250rpm.

The torque vs HP crossover point is a function of what scales are used. To cross at 5250, the scales must be HP and FT-lbs. Other units of measure will cross at different RPMs.