I am looking for advise on what you guys do during your rides. I find that after I get cranked up I move into a pattern. Two pedal revs in and two out. I try to breath in through my nose and out of my mouth. However, I find that I have to take a gulp now and then. I also occasionally realize that I have drifted off and am not pattern breathing. When I road ride I am usually pushing for speed over a 20 mile distance.

What do you guys do / reccomend?

Yup, I also try and get into some sort of rhythm relative to my pedal cadence regarding my breathing. However, I try and take in air more slowly, and exhale more quickly. If my cadence doesn't match my breathing well, I try and get a song in my head.

I guess that's better than installing a bigger nose.

I suck wind. I have never in any sport been able to control breathing. Definately my number one weekness. It might also have to do with the fact you can't get a consistent rythm in pedalling when doing technical offroad.

Your body knows how much O2 you need in your blood and cells, and how much CO2 and other waste you need to get rid of, so your breathing will vary to compensate for that. So what I'm saying is, breathe the way you feel you need to breathe, whatever is natural and comfortable. I've found that often the natural breath rate for me is very rhythmic during an intense workout, but I wouldn't try to set any specific rhythm and not allow any variation.

There are specific techniques for breathing and I see pretty much every pro employ the type of control that can help you ride more efficiently. It takes some getting used to but when you look at swimmers, you must agree that breathing while swimming fast is a learned skill.
As with your legs, cadence, muscular endurance, sprinting, bike handling, climbing and breathing-- controllable physical activity can be trained to be more efficient.
There actually is alot written about it and since breathing is basically fuel for your blood, the most efficient way to do it will definitely improve your speed. It feels very unnatural at first but do you remember the first time you tried to swim and breath?

Concentrate on emptying you lungs when you breath out as stale air wont get any oxygen into your blood. Then, when you suck the air in you will have lungs full of fresh air.

When I'm commuting I try to time my deep and shallow breaths in accordance with minor fluctuations in smog levels depending on the position and type of motor vehicles around me. It's harder than it seems, but I'm sure I'll get the hang of it eventually.

I tend to draw in air and keep my mouth as close to closed as I can sort of sipping. Unlike the others, this is not an adaptation to some sort of atheletic ideal, I just don't want a bug in the air intake.

I am not home, so I can't look this up, but do a check on google for yoga breathing.

I have used yoga breathing in the past, and found that it has tremendous advantages. As you become more efficient at deeper breathing, you'll find that you'll be able to bring in more oxygen and train more efficiently with the increase in oxygen. Not to mention it keeps you calmed and grounded at times when your training becomes more intense.

I'll check for some of the reading I have when I get home and post some tapes and books I've read on deep breathing.

I concentrate on exhaling and the inhaling is automatic.