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HJey guys: Old thread but very relevant. The 14 wins on displacement yes, perhaps refinement among other things, etc. but shave off some of those cubes and what's really underneath.

zx12r
Wet weight: 545 lbs. 91.2 lb-ft at the wheel. 1.24 lb-ft per in3 (73.2in3)

zx14r
Wet weight: 593lbs. 113.2 lb-ft at the wheel. 1.28 lb-ft per in3 (87.9in3)


Difference in torque per in3: .04 lb-ft to the zx14r. At the same displacement (73.2 cu in) of the zx12r this would amount to 93.69 lb-ft (1.28) * 73.2 for an increase over the zx12r by (93.69-91.2)= 2.496 lb-ft. or roughly 3% more

Difference in weight: 8% less goes to the zx12r
At the same weight and displacement of the zx12r the zx14R would have to make (1.08 * 91.2) = 98.496 lb-ft to match the zx12rs power to weight. Therefore at the same displacement as the zx12r, the zx14rs 93.69 lb-ft is (98.496-93.69) = 4.8lb-fts or roughly 5% less.


Although power to weight is usually between hp and weight, here let's use torque. The difference between the two, .03-.05 = -.02 = 2%. Older technology does not equate to less performance

All my #s for both bikes are from wiki.


Why are you comparing torques? Those are meaningless on a per engine size basis. Just think of torque as how much power an engine makes PER REVOLUTION. Torque does however give you a good idea of how friendly the bike will be - a bike with little torque will require much higher engine speed to produce the same power.

If you look at HP per liter, the 12R wins.
12R: 162.7HP => 135.7 HP/L
14R: 191.7HP => 133.0 HP/L

This is pretty typical. Smaller engines can rev super high and as a result, make a lot of power for their size. This is why the s1000rr only has 10HP less than us despite the 14R being 44% bigger.


The head design is supposedly much better than the 14’s. I can’t verify that.

Sent from my iPhone using Tapatalk

Where have you guys heard this? Typically engineers don’t get rid of good designs, especially when they have competition from other companies.
 

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Huh... I heard the answer is "because a vest has no sleeves", but I suppose your answer is just as good.
And the way I used it, just as relevant.
Like the old joke where the guy asks the philosopher "how is your wife?" and the philosopher answers "compared to what?"
 

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Why are you comparing torques? Those are meaningless on a per engine size basis. Just think of torque as how much power an engine makes PER REVOLUTION. Torque does however give you a good idea of how friendly the bike will be - a bike with little torque will require much higher engine speed to produce the same power.

If you look at HP per liter, the 12R wins.
12R: 162.7HP => 135.7 HP/L
14R: 191.7HP => 133.0 HP/L

This is pretty typical. Smaller engines can rev super high and as a result, make a lot of power for their size. This is why the s1000rr only has 10HP less than us despite the 14R being 44% bigger.






Where have you guys heard this? Typically engineers don’t get rid of good designs, especially when they have competition from other companies.
Too bad they don't have hp per liter race classes. More telling for real-world use is the torque graph of each.
ZX12R-91.2 ft.lb. at the rear wheel 76 ft.lb/liter
ZX14-103 ft. lb. at the rear wheel 76 ft. lb./liter
ZX-14R-113 ft. lb.at the rear wheel 78 ft. lb/liter
 

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Why are you comparing torques? Those are meaningless on a per engine size basis. Just think of torque as how much power an engine makes PER REVOLUTION. Torque does however give you a good idea of how friendly the bike will be - a bike with little torque will require much higher engine speed to produce the same power.
the reason I did torque is because I don't think i've seen it anywhere else. every does power/weight.

If you look at HP per liter, the 12R wins.
12R: 162.7HP => 135.7 HP/L
14R: 191.7HP => 133.0 HP/L

This is pretty typical. Smaller engines can rev super high and as a result, make a lot of power for their size. This is why the s1000rr only has 10HP less than us despite the 14R being 44% bigger.
Precisely, better ve.



Where have you guys heard this? Typically engineers don’t get rid of good designs, especially when they have competition from other companies.
Well have to let those guys chime in.
 

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Why are you comparing torques?-TurboTJ

Horsepower sells motorcycles and torque wins races. He who flies with the most torque wins

The thread is about comparing the 14 to the 12R, so their torque figures are pertinent.

The 14 has more rear-wheel torque than the 12R. The 14R has more rear wheel torque (and better torque per liter) than either. Guess which is fastest and which is slowest?
 

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Too bad they don't have hp per liter race classes.
They do, it's called bench racing.


More telling for real-world use is the torque graph of each.
ZX12R-91.2 ft.lb. at the rear wheel 76 ft.lb/liter
ZX-14-113 ft. lb.at the rear wheel. 83 ft. lb/liter

I think the consensus at this point is the 12 you can get into for less out of pocket :wink2:
 
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