Is there a scientific way to find your ideal cadence?? What criteria I use to determine it?? (You can tell I am new to cycling and on a learning stage). Any help or direction pointing will be greatly appreciated.

I think the only way to really determine it is to see what's comfortable for you. The more you practice pedaling quickly the more comfortable you'll become with higher cadences. For flats you should strive for a cadence between 90-120 RPMs, this will put more of the burden on your cardiovascular system rather than your muscles.

@ vision646: Thanks for the info. I will use the range you gave as a starting point and adjust accordingly. Thanks!!

Using a combination of a power meter, a trainer, a heart rate monitor, maybe a pulse/ox, and a computer for data collection and analysis... You could theoretically setup test parameters and see what cadence results in the best output w/ the least impact over the longest period of time. Not easy or convenient. Most common is lots of riding on varied road conditions at different cadences to "feel" what is best. Using some of the tools like an HRM should help you match "feel" with more tangible data to decide...

It depends on you definition of ideal. If you want to be more efficient lower cadences around 60 are appropriate but might be harder on your knees. If you want to be able to respond to accelerations better for competitive rides then a higher cadence is better. Everyone is different and eventually settles into a self-selected comfortable cadence suitable for the riding they do.

People spend too much time thinking about cadence. If you're starting out just ride lots and experiment with different cadences under different conditions. You'll figure out what is comfortable.

I think cadence is very much an individual thing. Greg Lemond tended to ride a cadence in the low 80s. When he was active, people tended to emulate him. But Eddy Merckx averaged a cadence of something like 115 when he shattered the 30 mph avg record for the hour time trial. I am not going to say that Lemond and Merckx did not know what they were doing. It would be like saying that if they rode the "right" cadence, who knows what they could have accomplished?

I ride at over 100 rpm because it just "feels right". I would suggest try a number of cadence levels and see what you settle into.

The additional problem is that there is a period of adjustment to a new cadence which IME lasts at least a couple of weeks. That greatly complicated the task of, for instance, doing hill repeats at different cadences and watching the power meter or distance/time. I would try varying the cadence by a small amount, maybe 3 beats, and checking that, before deciding anything. Also, best cadence varies a lot with power output/HR. Higher outputs require higher cadences or you only last 5 minutes. Low outputs, like resting, and an 80 cadence might be the thing.