CC's vs horsepower


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Old 03-11-03, 05:33 PM
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CC's vs horsepower

whats the difference between CC's and horsepower? for instance,what would 493cc average out to in horsepower?which is more?
 
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Old 03-12-03, 03:50 AM
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CC is the size of the engine, hp is the power the engine makes from it.

Depends on the bike, sportbikes make far more horse power from each CC than any other type of engine, cruisers and other v-twins tend to make more tourque, but can't rev nearly as high and weigh substantially more.

My 900cc bike puts out about 130 hp stock, that's as much or more than most car engines twice the size.
 
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Old 03-13-03, 12:47 AM
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There is really no way to determine HP just by cc's. CC stands for Cubic Centimeters, which is the unit used to measure engine size by measuring the volume of the bore from the top of the piston at the top and bottom of its' stroke. Generally, hp increases with CCs, but not always, especially in cross applications. Carburetion, stroke, valve lift and duration, intake, timing, and other things affect the HP. That is why two different engines with the same CCs might have a large difference in HP.
 
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Old 03-19-03, 05:52 PM
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thanks for the help. ive been looking at a 4wheeler that has 493cc and was just wondering around how many horsepower that equaled too. thanks again
 
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Old 03-19-03, 06:26 PM
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An 'old' rule of thumb was - about one hp for every 10 cc's.
Thus your 500 cc atv s/be about 50 HP +/-.

fred
 
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Old 03-31-03, 06:13 PM
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CC vs HP

There is no real good way to determine HP vs CC. I had a '86 KX 500 that was 72 HP, I now have a '90 CR 500 that is 63 hp, the 63 feels stronger than the 72. I have ridden many bikes with the same displacement and less HP that felt stronger than the higher hp. Torque curve, gearing, correct carb settings, make all of the difference. There are so many design differences that will effect the outcome of the HP rating. Some motors have power valves, some don't, it all makes a difference. There is only one rule of thumb...."there is no replacement for displacement"! Just point, twist, hang on!
 
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Old 04-01-03, 11:33 PM
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That's a good point...the differences in your 63 and 72HP engines. Many people think that more horsepower means faster, quicker off the line, more pulling power, etc..., but that's not really the case all the time. You could have an engine rated at 50hp at 4000rpm, compared to a 35hp engine rated at 1500 rpm. If you want speed, the 50hp engine would be the ticket. If you want torque, the 35hp engine would outperform the 50 by far. Then, consider gear ratios, tire sizes, and other factors and you can accomplish all sorts of variations. I have an 11hp engine geared waaay down on a small riding mower frame. It will pull so hard that It will pick the front end straight up in the air if the load won't move. I have pulled a truck with trailer attatched with it with ease! The same mower, before gearing down the ratio, would go much faster, but wouldn't pull a knot in your shoelaces.
 
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Old 04-02-03, 05:41 AM
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Think of engines as big air pumps. The more air the can move the more power they can produce. The formula for horse power if torque is know is (Torque x rpm ÷ 5252 = horsepower), notice that CID, or CCD is not included. There are many factors to consider when think about the HP per CC ratio. First thing that effects this is the volumetric efficiency of the motor. If the cylinder is filled with air that is the same pressure as the air out side the cylinder the engine is said to have 100% V.E., when the pressure is higher like with supercharges and turbo’s the motor can get up to 130% V.E. most of the time you will not find engines not running on special fuel with a V.E. of over 130. Compression ratio is combined with V.E. go along way in determining how effect of a “air pump” the engine is. The motors ability to do work is not only measured in horse power, but also in torque. Torque is best thought of as twisting force, or ability to get something moving, horse power on the other hand, is how fast work can be done. If you have two 50hp motors but one makes 40lbs/Ft of torque and the other one makes 30lbs of torque, the 50HP-40lbs/Ft motor will fell more powerful, but thy are both 50hp engines. If you add lower the gears (numerically higher), you increase torque but limit how high the engine can rev when attached to the drive train, therefore limits how high the engine can rev, so that might limit horse power. Also how effectively the vehicle is geared for the motor’s torque and HP curve. When I evaluate a motorcycle or race car, I look at the weight of the vehicle divided by the HP. But I also look at the HP and torque curve to see how flat they are and where the peak, where the maximum HP and Lbs/Ft are and if that is where it will be usable. Take for example two different 4-wheelers; one will be used for farm work the other will be used for desert racing. The one for farm work needs to have Torque and HP low in it RPM band for pulling and climbing things, a good motor for it would make 40HP and 40Lbs/Ft at 1500RPM. For farm a work this would fell like a powerful machine. The desert racer would make more like 60HP and 45Lbs/Ft at 6000RPM this quad would fly over the dessert. But even though the desert racer is technically more powerful it would fell like a lawn mower when used for work and utility purposes. But the 40HP and 40Lbs/Ft quad would feel like a rock if used for racing. I hope that give you a better idea of what to consider when comparing a vehicles with another and why you would want to look at the certain numbers.
 
 

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