psycho1122
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posted December 14, 2005 08:30 PM
quote:
Doug, that seems low (180) to me. I have a 2000 zx-12 with a Muzzy full exhaust, PC-IIIr, K&N filters and no Kleen air and it kicks out 175 RWHP - only 5 more for the '14?  .
These mods on the 14 should yield low to mid 190's
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supra5677
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posted December 15, 2005 09:59 AM
remember folk drastically increasing the stroke rather than the bore adds torque first horsepower second. Remember torque is the enemy of horsepower, and horsepower is the enemy of torque.. This is why a 1287 with properly degreed cams yields 195-200 horsepower with a pipe of course.. I saw a magazine guessing 195 crank horsepower, with 12% drivetrain loss yields app 172@ the wheel.. we shall see. I wish kawasaki would have kept the small stroke and gave a bigger bore with more compression..
I think another nastier badder bike is coming in 07 or 08. Remember Kawasaki discontinued 3 bikes to make the 14.. that leaves room for one more..
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fullzx12r
Zone Head
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posted December 15, 2005 11:04 AM
is it possible to do a CONCLUSION for me, i'm not a good english reader... i'm a french...
doug, could you please resume your impression of the engine of this ZX-14 ?
thanks a lot guys 
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zx-12r 01'
zzr 1400 06'
hayabusa 08'
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Y2KZX12R
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posted December 16, 2005 01:24 PM
Remember, compared to a long stroke engine of the same displacement and all other things being equal, a short stroke engine suffers a bigger penalty from an exhaust restriction. This is why a busa doesnt gain as much power as a 12r when both bikes have a pipe put on them. So i dont think you will see quite as much gain as the 12r saw when you put a pipe on it. And like doug said, with two cans you are flowing more air volume.
Note the exhaust valve angle is greater than the intake. The 12r was similar in that the intake valve angle was less than the exhaust. Still no cap screws on the rods.
The injectors look like a lucas/delphi disc type. ?
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trenace
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posted December 16, 2005 04:23 PM
quote:
Remember, compared to a long stroke engine of the same displacement and all other things being equal, a short stroke engine suffers a bigger penalty from an exhaust restriction. This is why a busa doesnt gain as much power as a 12r when both bikes have a pipe put on them. So i dont think you will see quite as much gain as the 12r saw when you put a pipe on it. And like doug said, with two cans you are flowing more air volume.
Good point, that I should have remembered and taken into account above but failed to do so. So maybe I should have said pipe + PCIII + filters may be worth probably more like around very roughly 10 hp, not the roughly 15 that I suggested before.
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Y2KZX12R
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posted December 16, 2005 05:21 PM
Yea you may be right. I have a fealing we will know in a few more months.
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dougmeyer
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posted December 16, 2005 05:22 PM
Supra,
I'm not pickin' on you, I'm really not, but your last post simply perpetuates a common misconception with no basis in fact.
An engine creates only one motive force and that's torque, measured, as you know, in pounds of force applied per foot (lbs.-ft.) .Make that force act in rotation, over time and you need to multiply it by the rpm. Divide that by a constant (5252) and you get a number we call horsepower. It's simply torque applied over time and it's based on the amount of weight a horse could be expected to lift ione foot in an hour, which is pegged at 33,000 pounds.
Horsepower is ALWAYS secondary since it's only a calculation made from the available torque.
It is another common misconception that long stroke always = torque. Not true.
This is simply the result of the fact that the design limits of a long stroke engine , namely piston speed "limits" keep it from revving high enough to create any high hp numbers.
(rememeber it's torque x rpm / 5252). Long stroke engines simply can't be built to rev high enough to create any really high hp numbers. (comparitively speaking)
When you build an engine that needs to fit in a certain space, like under the backbone of a motorcycle, you have a maximum stroke that will fit. If you want to increase the amount of power that design can produce without lengthening the storke, you can:
1. make the bore bigger
2. add cylinders
3 add rpm (without breaking the piston speed design limits)
4. pack more air (and fuel) in it.
Torque the enemy of hp?
On the contrary without torque there IS NO horsepower.
I wrote a long piece on this once that more clearly explains it. I'll try and find it and post it up next week.
Psycho- exactly.
Y2- Why do you recon that is?
D.
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Y2KZX12R
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posted December 16, 2005 06:22 PM
Doug, recon what? why short stroke engines are more suseptable to power losses from exhaust restrictions? I never really thought about that. I'll take a stab at it.
Short stroke engines rev higher and rely more on valve overlap, scavenging, and properly tuned intake and exhaust tracts to get high VE at high rpms.
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dougmeyer
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posted December 16, 2005 07:25 PM
Makes sense. I never considered it much either. I'll keep thinking about it, though..... :-)
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CrotchRocket
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posted December 16, 2005 07:27 PM
Jim, I think Doug is refering to the injectors look like a lucas/delphi disc type. ?
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blubyu
Expert Class
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posted December 17, 2005 07:50 AM
OK..OK...You guys did all the measurements...and the close ups...will the motor fit in a 12 frame? That's what many of us really want to know!!
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robmuzzy
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posted December 17, 2005 08:11 AM
Stroke has nothing to do with it. CC X RPM = volume of flow. short stroke engine of same displacement will probably rev higher. Therefore more exhaust flow. More exhaust flow means the exhaust system is more critical.
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Y2KZX12R
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posted December 18, 2005 01:44 PM
Rob that makes sence. But what if you restricted the exhaust flow of two identical displacement zx12r engines but with drasticaly different bore stroke ratios and cams. Both engines are at the peak hp figure for the longer stroke engine, lets just say 10,500 rpms. The two engines would make different hp levels at that perticular rpm because of thier differences. But if you added the same restriction disk to the exhaust tip, would the short stroke engine loose more hp?
Now rev the short stroke engine to its peak of lets say 11,500 rpm and I could see the increase in total exhaust volume creating more back pressure and robing a higher % of the HP, as you stated.
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CrotchRocket
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posted December 18, 2005 06:07 PM
 Goes to show ya what I know
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capt10ed
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posted December 19, 2005 05:36 AM
Mr Meyer Having looked at the engine what is the likely hood that the 14 engine could be swapped into in my opinion the nicer looking zx12r frame? according to what I read it has the same basic dimentions.
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with a best of 208.1 in 1.5 miles
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fish_antlers
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posted December 19, 2005 05:41 AM
quote:
Mr Meyer Having looked at the engine what is the likely hood that the 14 engine could be swapped into in my opinion the nicer looking zx12r frame? according to what I read it has the same basic dimentions.
not sure why you'd want to do that.. for all intents and purposes the 14 appears to be a 12 with different bodywork... would be easier to change the plastic...
or just ride the thing.
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dougmeyer
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posted December 19, 2005 08:19 AM
No point. The 14's better in many ways. Let's face it, a good fabricator can fit just about anything into something, but whether you might end up with something better is not always assured.
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supra5677
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posted December 20, 2005 10:49 AM
In my humble opinion the busa makes less horsepower than the 12 because of milder cams, less compression, and a longer stroke which limits its piston speed... a 55.4 mm stroke will always be able to spin faster than a 63mm stroke...
supra
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oldkawboy
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posted December 22, 2005 08:33 PM
Everybody knows them 'Boosa's are the world fastest production motorcycles because of them two mufflers, just ask the folks at Guinness......LOL
Seriousy though, twin pipes do have a purpose.
Dan
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Y2KZX12R
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posted December 25, 2005 09:06 AM
Exactly. The 12r revs higher and so it makes more HP.
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trenace
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posted December 25, 2005 11:58 AM
 Edited By: trenace on 25 Dec 2005 12:24
Believe it or not, that's the point that I wound up deciding to take a hiatus from another board on, the question of effects of displacement increase achieved by bore increase (assuming not already too oversquare, which was hardly the case for the motor in question) ) vs stroke increase, with the stroke increase being less effective (except in that instance), for precisely the reason you and supra say.
A moron was arguing that bore increases were nearly worthless, while stroke increases were way better for more peak hp; that a mm of bore increase gives less gains (despite giving about double the displacement increase) than a mm of stroke increase, as something you can pretty much take to the bank; and that a 60 cc displacement increase from boring is allegedly worth only 2 hp as what you should expect.
I just couldn't take it anymore.
Indeed, stroke increases generally improve peak hp by less than the percentage increase in displacement, precisely for the reasons you stated. One "rule of thumb" is that stroke increase improves peak hp by only about the square root of the increase, rather than directly. So for example, if the ZX-14 had no other change but stroking and appropriate remapping, an estimate for the improvement yielded from the 55.4 to 61 mm increase (10.1%) would not be that 10.1% but rather only about 4.9%.
Or about 8 hp from only the stroke increase.
Because of the fact that while displacement increases, the speed of the motor decreases proportionately or nearly so. Actually, if the tachs and limiters are equally (in)accurate, 11 thou on the new motor is a little higher piston speed than 11,500 on the Twelve, would actually correspond to about 12,100 rpm on the Twelve. For this reason, the power increase from the stroking aspect may be a little better than figured above. There is also a small bore increase as well as an entirely new head, different exhaust, etc. In any case 200 hp+ at the crank is certainly believable.
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speedgene
Zone Head
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posted December 26, 2005 12:24 PM
I can see a lot of meat can be removed where the above forefinger and thumb are showing (the cylinder thickness) in the photo of this thread... (Example: "Look at the cylinder. One piece, cast with.....").
I'm not a machinist, engineer, or performance engine builder, but where that forefinger is, has anyone looked at the cylinder wall thickness on the exhaust side? (See first photo in this thread). Looks like the cylinder taper will be removed by more than half for easy ring installation if any bore is done.
How much will there have to be removed to compensate for the re-installed layer of the chrome-composite? What happens to the (bored deeper walled) squish band, and how will this reshape the combustion from stock? If it has an O-ring to seal the head, and cylinder (like an '03 KX125), where is the black round dot in the engine cut-away? Where is the head gasket at all?
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