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They do, it's called bench racing.





I think the consensus at this point is the 12 you can get into for less out of pocket :wink2:
No surprise there, as the last 12R was made in 2005. By 2030, when it reaches antique status, it may not be so cheap.

Personally I'd like a 12R with a bar kit and a 14R engine. Someday a blown-up 12R may fall into my lap and it'll happen.
 

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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?


Some Harley’s have as much torque as us. Guess they’ll be just as fast in a race?

I respectfully disagree. Horsepower is really the only thing that matters. If you need to rev to 20,000RPM’s to achieve say 300 HP, then you have very little torque (because of the engine speed) but 300HP is 300HP. Torque is a dependent variable of HP and RPM. People treat it like it’s some magic property this sits side by side with HP.

Torque = Power/(2 x pi x rotational velocity)
 

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Precisely, better ve.


This may be the case, but it’s not implied by more HP/L. You can have worse volumetric efficiency but make more HP/L for a variety of reasons. For example, if one engine can rev significantly higher, it will likely make more power even if the VE is worse.
 

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This may be the case, but it’s not implied by more HP/L. You can have worse volumetric efficiency but make more HP/L for a variety of reasons. For example, if one engine can rev significantly higher, it will likely make more power even if the VE is worse.
Well I thought we were talking just about the two bikes cid to cid, stock/ unmodified. If you think it maybe the case, perhaps we're not in complete disagreement. However you look at it, I'm fine with what I have. When someone is out for that every bit of hp, I think there's nothing wrong with that either.
 

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Some Harley’s have as much torque as us. Guess they’ll be just as fast in a race?

I respectfully disagree. Horsepower is really the only thing that matters. If you need to rev to 20,000RPM’s to achieve say 300 HP, then you have very little torque (because of the engine speed) but 300HP is 300HP. Torque is a dependent variable of HP and RPM. People treat it like it’s some magic property this sits side by side with HP.

Torque = Power/(2 x pi x rotational velocity)
I can tell you've never ridden around Harleys. They are pretty quick until they run out of breath. One of my friends had a Low Rider with a 130hp S&S engine. If I kept it under 8K rpm, he had no trouble keeping up.

Actually, horsepower is dependent on torque, not the other way around. HP=Torque X RPM divided by 5252 1 horsepower=33,000 lbs. ft. of torque per minute


http://www.epi-eng.com/piston_engine_technology/power_and_torque.htm
 

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I can tell you've never ridden around Harleys. They are pretty quick until they run out of breath. One of my friends had a Low Rider with a 130hp S&S engine. If I kept it under 8K rpm, he had no trouble keeping up.

Actually, horsepower is dependent on torque, not the other way around. HP=Torque X RPM divided by 5252 1 horsepower=33,000 lbs. ft. of torque per minute


http://www.epi-eng.com/piston_engine_technology/power_and_torque.htm
That's the way I learned it. When operating a compressor for example and having to calculate the power requirements to generate x amount of output, that's the way it's done.

The statement of "Horsepower is really the only thing that matters" I'm not going to say is wrong. But is that really the only thing that matters is kind of one of those questions perhaps could use a revisit and see if the answer remains the same :smile2:
 

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I can tell you've never ridden around Harleys. They are pretty quick until they run out of breath. One of my friends had a Low Rider with a 130hp S&S engine. If I kept it under 8K rpm, he had no trouble keeping up.

Actually, horsepower is dependent on torque, not the other way around. HP=Torque X RPM divided by 5252 1 horsepower=33,000 lbs. ft. of torque per minute


http://www.epi-eng.com/piston_engine_technology/power_and_torque.htm


The equation looks better as Torque = HP x 5252 / RPM :)

The reason I say it’s the only thing that matters is it’s the only thing that contributes directly to acceleration. If we differentiate the kinetic energy equation, we get that power = change in kinetic energy over time. Assuming we don’t change in mass, that correlates power directly to acceleration. There is no torque variable in this equation. Acceleration is only a function of power (horsepower) and mass.

You can only take torque into account by adding engine speed in.


That's the way I learned it. When operating a compressor for example and having to calculate the power requirements to generate x amount of output, that's the way it's done.

The statement of "Horsepower is really the only thing that matters" I'm not going to say is wrong. But is that really the only thing that matters is kind of one of those questions perhaps could use a revisit and see if the answer remains the same :smile2:


But let’s say that we put a gearbox in front of the compressor input (like with the H2R). The torque will change depending on if you measure pre or post gearbox but the power will stay (relatively) constant. Torque will change with shaft speed but power remains the same for doing a given amount of work with the compressor.


Power is the ability to do work in a given amount of time (such as accelerate a mass). Torque simply says what shaft speed you are doing that work at.
 

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The equation looks better as Torque = HP x 5252 / RPM :)

The reason I say it’s the only thing that matters is it’s the only thing that contributes directly to acceleration. If we differentiate the kinetic energy equation, we get that power = change in kinetic energy over time. Assuming we don’t change in mass, that correlates power directly to acceleration. There is no torque variable in this equation. Acceleration is only a function of power (horsepower) and mass.

You can only take torque into account by adding engine speed in.






But let’s say that we put a gearbox in front of the compressor input (like with the H2R). The torque will change depending on if you measure pre or post gearbox but the power will stay (relatively) constant. Torque will change with shaft speed but power remains the same for doing a given amount of work with the compressor.


Power is the ability to do work in a given amount of time (such as accelerate a mass). Torque simply says what shaft speed you are doing that work at.
I would like to see a dyno curve that illustrates what you mean. Torque is force and force produces horsepower. Horsepower is an expression of work which is torque over a period of time. You can flip the formula anyway you want but it's still the same.
 

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I'll use this analogy: MotoGP engines. Most produce in the neighborhood of 250bhp. But the only way to use it is with electronic controls that keep torque output steady enough for the tire not to spin and as the machine gains traction going from full lean to full upright. The electronics only feed in as much torque as the tire can put to the pavement (ideally) and a flat 250 bhp with no electronic mitigation in a 335-lb. motorcycle would be nigh onto uncontrollable. So horsepower, while important, is definitely not the only thing that counts. you can have as much bhp as you can get, but putting it to use is dependent upon torque at the tire/pavement interface.

I saw a perfect example at Indy MotoGP a few years ago; The Honda Team, Marc Marquez and Dani Pedrosa came out of the infield and onto the fast part of the track neck-and-neck. As Marquez dove to the inside, his footpeg snagged Pedrosa's rear wheel speed sensor wire and disconnected it. When they emerged onto the front straight, they hammered the throttles and Pedrosa was immediately spit off in a spectacular highside that he was lucky to escape unscathed from. Both had the same horsepower, but the only thing that mattered was the torque put to pavement.
 

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My only point here is that HP is what correlates with acceleration. I can derive all the equations if you guys are interested. Harley’s make massive torque and we all know how slow they are. They do this by making HP at low RPM’s, which as our equations show, results in high torque.

Many gas turbine (jet engine) vehicles make high HP but at high (think 55,000RPM) engine speeds. This results in very little torque at that speed but also gives crazy acceleration. If the engine makes power down low, it may also have high torque.


To put this another way, if I put an accelerometer in my car and accelerate on flat ground, I can estimate my horsepower directly. To get torque, I need to know what RPM I’m at. This is why I say that HP is what matters because it directly correlates with acceleration. Not torque.


I would like to see a dyno curve that illustrates what you mean. Torque is force and force produces horsepower. Horsepower is an expression of work which is torque over a period of time. You can flip the formula anyway you want but it's still the same.


Torque is not force. Torque is the cross product of your force and distance vectors.

I think we are getting lost here. A dyno can only measure HP of the engine, not torque without some engine speed measurement. It may do this by measuring how much something is torqued (such as a water brake). Then, once you tell the dyno what the engine speed is (typically by putting a sensor on the spark plug cable) you can resolve engine torque. It must know the engine speed to calculate engine torque. This is for a chassis dyno of course.

I'll use this analogy: MotoGP engines. Most produce in the neighborhood of 250bhp. But the only way to use it is with electronic controls that keep torque output steady enough for the tire not to spin and as the machine gains traction going from full lean to full upright. The electronics only feed in as much torque as the tire can put to the pavement (ideally) and a flat 250 bhp with no electronic mitigation in a 335-lb. motorcycle would be nigh onto uncontrollable. So horsepower, while important, is definitely not the only thing that counts. you can have as much bhp as you can get, but putting it to use is dependent upon torque at the tire/pavement interface.



I saw a perfect example at Indy MotoGP a few years ago; The Honda Team, Marc Marquez and Dani Pedrosa came out of the infield and onto the fast part of the track neck-and-neck. As Marquez dove to the inside, his footpeg snagged Pedrosa's rear wheel speed sensor wire and disconnected it. When they emerged onto the front straight, they hammered the throttles and Pedrosa was immediately spit off in a spectacular highside that he was lucky to escape unscathed from. Both had the same horsepower, but the only thing that mattered was the torque put to pavement.

This kind of confuses the argument a bit. We are talking torque at the engine (as a measure of how good the engine is) not torque at the rear wheel. For what you are talking about, you are correct. Torque at the rear wheel is what decides many things (such as going into a wheelie, burning out, etc.). This isn’t as relevant because it has to go through the transmission which typically increases torque in lower gears at the rear wheel. I can use a transmission to develop almost any torque at the rear wheel.


Torque is science. Horsepower is scientology.

Haha sure. Horsepower is power which is energy over time. It can be just as easily measured in Watts, as in a 75W lightbulb. There is ~745 Watts per HP if I remember correctly.
 

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OK, simply put, torque can exist without movement but horsepower (work) cannot. Torque+movement (rpm) produces horsepower.

So to say torque means nothing or less compared to horsepower is ludicrous. Horsepower cannot exist without torque.
 

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Torque is a number to relate to how much work something can do... horsepower is how fast can it do that work... to win races, you need both.. enough torque to move your ride down the track, and enough hp to do it in a timely manner...

J
 

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OK, simply put, torque can exist without movement but horsepower (work) cannot. Torque+movement (rpm) produces horsepower.

So to say torque means nothing or less compared to horsepower is ludicrous. Horsepower cannot exist without torque.


What people new to owning a motorcycle should do if they haven't already is take a small engine repair class. Then pick up a small engine open it up and become familiar with how it ticks. In the long run it can amount to greater enjoyment in having the knowledge, and skill to do the maintenance on your terms and time. There's a certain satisfaction in knowing what's between your legs. I've said this before perhaps it's worth a repeat. With all the hp in the world there's one contender you lose sight of and there's no amount going to help.

 
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