If I were to race a stock '93 Suzuki Katana against a stock '03 R6, I'm guessing that the R6 would win. My questions is this; what factors determine which bike beats another if they have the same engine capacity (600cc)? To restate the question, I'd like to know what makes one bike with a 600cc engine faster than another with the same size engine.

Man there is soo much that affects anythings speed. Ok so you know 600cc's is a displacement, an empty space really. What makes it go is how well it can combust and things that affect it like if the parts are light and fit perfectly like they suppose to and are fully lubericated, and the faster it can rev the more power it can generate. Then starts thowing in the size of fuel injectors to regulate how much fuel you can put in the mixture, and then a fuel pump to push that, more fuel, more combustion. That will create engine horsepower. Now you got gearing, different gearing can make different speeds and how fast you can reach that speed. And then you have weight. The lighter the bike the less the engine has to work to accelerate. And at high speeds things like Tires and aerodynamics come into play. Those are just a few things in short that can affect the speed and acceleration of the bike.

I am in no way an expert or have i scratched the surface on what there is to know about bikes, but i know that gearing plays a key role in cars. The main factors i would say would be gearing, the amount of fuel/air thats being comsumed, the ability of the bike(not wheelieing when gas is cranked) and many other things play in this. Same as a 600 R6 would beat a 1700 roadstar. Many many things are factors.

OKay first let's compare the vehicles power, weight, intended design. The R6 in '03 made roughly 104hp and the katana (taking and educated guess) made 75hp. Next you have weight, an r6 weighs 425lb and a katana weigh 600lb. Focus of design, r6 speed/win races at the track, while the katana was meant to commute and be comfortable.

So back to the power. You have a bike that weighs 100lb less and makes 35% more horsepower. The weight alone points out a difference. Why do you think racers try to strip all excess parts and weight?

Then you have intended design. Suzuki didn't engineer the katana to squeeze every bit of power out of the bike. They needed something that would last forever and not break. Which explains why the bike was still oil/air cooled into the late '90s. It just wasn't pushing the envelope pf performance. Whereas the r6 makes pretty close to as much power as can be made.

Without going into an encyclopedia of differences this should give you the "Cliff's Notes" version.

Awesome, thanks a lot guys. All that information is very helpful!

Reiterating what NT said it has a lot to do with intake and engine geometry/parts. An R6 has things like forged pistons, lighter valve springs for a higher redline etc.. These things lead to less inertia and therefor less of a power as it is transfered through the drive train and to the wheel. I'm not to sure on this one but I think materials come into play as well. Different materials transfer heat differently and heat is another thing that causes horsepower loss.

Yea everyhting to the bike makes a difference, people like titanium cuase it can withstnad a high amount of heat without breaking down so you can push it harder and faster, basically making the block taking the beating, not the parts, then it really comes down how well you can keep it lubericated. But yea everything, from materials, to how tight tolerences are, and even now aerodynamics help increase speed faster and higher speeds and then keeps the bike stable and keep cool air flowing though the intake