Hey, can someone answer a few questions about ATV engines?

ATVs always have a number (displacement) in their name, like Raptor 660R. Under specs it says something like "660cc." The "cc" means cubic centimeters? What does that mean, that the engine size is 660 cubic centimeters? I understand displacement has little to do with horse power, other than bigger engines usually create more horse power.

An ATV also has "bore and stroke." The specs say something like "94mm x 64mm." What does that mean?

Then there's carbuetion. The specs say a name then something like "44mm." What does that mean?

Whats the "compression ratio" mean?

In the end, the weight of the ATV and horse power will determine speed?

Thanks for the help!

 

The amout of cubic centimeters is the size of the cylinder and/or piston in the engine.

The bore is the diameter of the cylinder and the stroke is the total movement of the piston from the top of the cylinder to the bottom. Longer stroke you get slower revs but more torque, shorter stroke you get quick revs and more top end.

44mm is the size of the opening on the carburator. Bigger number more air and fuel.

Compression is the amount space and/or pressure in the cylinder when the engine in on it's compression stroke. I don't exatcally know what the ratio is means...anyone?

Weight and HP do help speed, but gearing takes a good tole on it too. Higher gearing makes the bike rev slower but go faster top end, lower gearing makes the bike rev faster but go slower.

Hope this helps!! [img]i/expressions/face-icon-small-happy.gif[/img]

 

CC's means Cubic Centimeters and no not always does the # in the name mean the cc's usually it's 2 cc's less than what it says in the name.. I.E. the RAPTOR 350 is 348CC Bore is the width accross the top of the combustion chamber one side to the other.. Stroke is the movement of the piston up and down not sure on caberators.. maybe someone will revize what i posted.. and it's not always bigger engines produce mroe power it's the right combination of parts... speed is so complicated i prolly won't list all the factors to factor in but here's some ... Power, weight ,gearing, tire size, friction(wind,friction in the engine,chain,brakes,bearings) it all factors into the speed... mainly gearing and tire size it what u need to change o na quad to get it to go faster but there's those other little thigns that can give u more power if adjusted right...

 

compression ratio is the amount of space in the cylinder at the bottom of the stroke compare to the amount of space in the cylinder at the top of the stroke.

weight and horsepower will determine acceration. Gearing determines top speed.
the displacement is the amount the cylinder hold for example a 660 would hold .66 of a liter.

Hope this helps

 

Thanks!

 

hugh jazz