Kawasaki Z900RS

[Ulvetanna_imp]

Ok first off rideapart was wrong because there was no 15 DLX and there are likely no more than 300 14 dlxs (the only year it was made) in North America

The CB has been dynoed by many magazines and many members here so 85 rwhp is a figure I feel confident using (NOT at the crank).

http://www.motorcycle-usa.com/photo-gall...cond-ride/

I have not seen a dyno on a 900RS yet, but if the std 125 hp Z900 loses 12 hp on the dyno to the rear wheel and comes out at 113, that's what I am going to figure on (ie: a 12 hp loss). Surely the detuned RS isn't going to rate only 2 hp less. Using someone else's actual dyno charts is the only measure we can use isn't it? Can't trust the manufacturers to tell us the truth since they don't compare apples to apples. (rwhp vs crank hp for example.. dry weight, vs curb weight vs wet weight for another example) so we rely on magazines to weigh and dyno and quarter mile them for us and compare those figures.

https://www.google.com/search?q=dyno+cha...qukDl-zsM:

I used the 545 pounds weight from from the standard 13 and 14 models (yes the dlx is 30 pounds heavier but like I said, it was a one off model and there aren't enough of them in the country to use as a fair comparison)

I don't care what numbers you use, the Kaw is lighter and has more hp, but the difference is not as large as some would make it out to be. But in the REAL world, where we actually ride the motorcycles daily, FEW of us (at least few of us on this board from what I have read) are going to notice the difference in HP between the two (except maybe on rare occasions). If the CB's dyno chart shows more horsepower in the rpms I ride in and the RS's dyno shows a hp advantage only in the upper regions of the tach near the red zone where I don't ride, then the CB will actually be the more powerful bike in my hands. And even if the Kaw shows a couple hp advantage in that 3500-5000 rpm range, that really doesn't mean squat does it? That is exactly the situation I was in with my Gen 1 FZ-1 I was riding when the CB came out. The CB made more hp than the FZ in the 3500-5000 rpm zone I ride, but once the FZ hit 8000 rpms. there was a steep rise in HP up to the 13,000 rpm redline where it smoked the CB... but I never rode it there. For me, the CB was the more powerful bike.

Some guys (you maybe) like to ride around banging them off the rev limiter, but I would say generally speaking those that would buy this type of bike are of a certain demographic that got that out of their system many years ago.

If it isn't about the power, then why has it become about the power? If a guy wants power, get something besides a CB1100. If a guy likes the CB1100, buy one. I sure did. Who in the world ever said different?

"but that extra 25 HP and 80-pound weight difference"

more like 15 hp (stock CB dynos about 85 rwhp the new RS will dyno about 99 rwhp... the full bore Z900 only dynos 113 rwhp or 28 hp more than the CB)

the weight difference is 70 pounds (CB 545 lbs... RS 475 lbs)

Ok, for you guys with far more experience than me, how much can you actually feel that difference in power?

I mean my HD dynoed at 86 rwhp and 92ft/lbs tq, my Buell is listed at 103hp, 84ft/lbs tq (at the crank I suppose) and whatever the CB is and I'll be honest - I can't really tell that much of difference between them.

One thing to keep in mind is that the Z900R, and even the RS, are much quicker-revving engines than the CB1100's. The CB has a 9.5:1 compression ratio. The Z900RS has a 10.8:1 figure, much higher. The Z900R has an 11.8:1 compression ratio.

If you consider those values, along with far less rotating mass in the engine, and far less mass to accelerate, you can imagine that the Kawasaki is going to get with it pretty well.

In the link I posted to motorcycle.com's article by John Burns, he mentions that for all practical purposes, the RS accelerates about as hard as the R model because the torque curve is shifted downward about 1000 RPM, and the RS is geared lower as well. Of course the R will pull away above 9K RPM due to its 13 additional horsepower but for most riding you'll never be up there. Well, except for me and those other hooligans who haven't gotten it out of our systems, lol.

So heck yeah, you can feel it, big time.

Anyway, on any dyno or any scale, crankshaft or rwhp, avoirdupois or metric, abacus or computer, the CB1100 is a lot heavier bike with considerably less power than the Z900R/RS.

Spec sheets help sell bikes, no doubt about it.

Of course it's a shame we aren't talking more about the awesome CB1100RS which Honda did not bring the United States. But it's better than talking about the weather.
I just also wanted to mention that the SAE horsepower figures reported by the manufacturer to the government on a document called a "Manufacturer's Certificate of Origin."

The methods used to measure crankshaft horsepower are, and must be, standardized to meed federal regulations. They can't really be all over the map like one dyno to the next.

Everything has to be measured under controlled conditions and corrected for pressure, temperature, and relative humidity, for example.

We are going to see much more variation from one rear wheel dyno to the next.

If one was to knock off about 10 percent, it'd be pretty close.

[postoak_imp]

What kills the Z900RS for me is the foot position is too far back. It looks to be the same as the Z900. Also, I read a review that said the throttle was on-off like a light switch. That's definitely not what I want -- and it isn't retro.

[emptysea]

+1 on the peg position.

Otherwise, an interesting looking bike. I’ll stick with my 2013 CB1100, though.

[redbirds_imp]

The peg position seemed too far back for my likes also until I compared an image of the Z 900RS taken from directly above the seat-tank juncture on Kawasaki's site and compared it to my CB looking down from the same point. They appear identical to me. I'll reserve judgement on this until I can actually sit on a Z.

[Ulvetanna_imp]

What kills the Z900RS for me is the foot position is too far back. It looks to be the same as the Z900. Also, I read a review that said the throttle was on-off like a light switch. That's definitely not what I want -- and it isn't retro.

They're lower and further forward but you are absolutely right, this bike is no retro, only in looks. Retro calls for air-cooling. That's why the Royal Enfield looks really good to me right now.

Even the Triumphs are liquid-cooled, albeit with pretty deep fins.

The Z900RS is a modern standard all the way.

Compared to the CB1100, yes, the throttle is going to feel very responsive. Also the Z900RS is geared even LOWER than the Z900, which I though was a little strange, since the Z900 has very low gearing in 1-5. Sixth is pretty tall.

However the Z900 in any form is unbelievably smooth at 70-80 mph. Essentially zero vibration in the handlebars. I have never ridden a smoother bike, or one with a flatter power band.
I was wondering about the actual weight of the CB1100EX model.

Yes, the Rideapart article called the '14 Deluxe a 2015 model in the article's title, but the writer correctly called it a '14 in text. By any name or year, it's a Deluxe and comes in at 571 per the service manual.

My question is, isn't the EX even more "Deluxe" than a Deluxe?

It has the twin pipes, and yet another half-gallon of fuel.

Don't see how it could come in at 540 lbs like the Standard.

I guess I gotta dig around and see if anyone actually weighed the thing.

Beautiful bike, though. Impressive on the showroom floor.

Looks like it weighs 562 lbs if Motorcycle.com can be believed. That sounds about right.

[the Ferret]

all this discussion about weight and horsepower just blows my mind

If you complain about the low horsepower of a CB1100, how can you be happy with the horsepower of a Street Twin?

and if you ride a Sym Wolf 150, how can you not complain about the excessive weight of a Z900?

IMO if you like the bike, it's not too heavy for you to move around or put on the center stand, and it goes fast enough for you, there is no issue with the horsepower or the weight. Other that that we are just peeing up the wall for bragging rights with regards to weight and horsepower.

[emptysea]

Echoing Ferret to some extent here, but while I can see the attraction to the Z900, I don't see enough difference between it and my 2013 CB1100 to make a change.

[nhawk7504_imp]

Wow dealer near me ordered four! He does not sell much. Spoken for too he said. But he also has three Z1000s from the 70s/80s as well so... He is a fan. It really just comes down to whether you're a KAW fan or a HONDA fan or maybe both. It's lighter if women want to ride it, or those of us of WSBK size. It's certainly not enough to change. Tis a tad sportier.

[Ulvetanna_imp]

Wow dealer near me ordered four! He does not sell much. Spoken for too he said. But he also has three Z1000s from the 70s/80s as well so... He is a fan. It really just comes down to whether you're a KAW fan or a HONDA fan or maybe both. It's lighter if women want to ride it, or those of us of WSBK size. It's certainly not enough to change. Tis a tad sportier.

It's way sportier. There's a huge difference. For those who really like the CB1100, don't buy a Z900 because it's not going to be anything like the Honda.

A few things about the Honda to compare with the Z: the CB's engine revs slowly and smoothly, and the chassis is very stable and handles the open road considerably better. If you plan on touring or two-up, the CB is a much better motorcycle. The Z feels very light and compact by comparison; the center of gravity is extremely low on the Z, it feels much lighter than it is. By contrast the Street Twin, for example, which weighs almost exactly the same, feels much heavier. The Z will feel quite nervous compare to the Honda although in reality it is very stable.

The throttle response on the Z is going to be much more immediate and it's going to rev a lot quicker.

The Ferret called it on this point; there is little real-world difference in outright power between the Z900 and the Z900RS, they are both very strong and there is not much between them until you hit about 9K rpm. But the Z900 is really a pretty stupid fast motorcycle. In fact I would say it shreds, and has more low end than most super bikes, certainly more than a late-model ZX-10R or YZF-R1, as an example. The Z is geared very, very low.

I am still quite intrigued by the idea of the CB1100EX with the six-speed and that big air-cooled mill. I'll bet it's nice on the superslab.

[emptysea]

You should really buy the Z900. Soon.