I am about 3 months into cycling and went from 20 miles a week to70 (2x 20 & 1x 30). I have started to notice an increase in knee pain, it's not debilitating but it is enough to make me wince every now and then. I'm 6 feet 190 pounds at 36 and i consider myself fat and out of shape.

Is this pain normal and something that will fade away as i put in more miles or is this something related to the fit of my bike?

Knee pain is not normal although many people will experience it occasionally. It can be associated with an incorrect saddle height. Is the pain at the front of the knee or at the back? The former is frequently a result of a saddle that's too low while the latter from a saddle that's too high.

Also, evaluate the fore/aft position of the saddle. I reconditioned an old Fuji Special Road Racer, and didn't bother adjusting the saddle position when I took it for a test ride. My knees hurt for a couple of days, afterward. I blamed the '70s gearing and Pennsylvania hills, but, when I took it out, the next time, I noticed the saddle was too far forward. After moving it back about an inch, the hills were (slightly!) easier, and no knee pain. I may have to keep this one.

According to where the knee pain is can be a sign of poor fit, or poor flexibility/stretching.

Normally, knee pain in the front or back of the knee is seat height and position issue. Less often pain on the sides can be fit (Q factor), but more often is a sign of needing to do some stretching.

Man...we all know our own bodies more than anyone.
If I play basketball or some other sport actively, I get knee pain that evening.
If I put in some tough miles on my bike, by the time I get home, I have to use the railing to get me up the steps.

But here's the thing, if I hopped back on my bike and loosened things back up, it would go back to normal and feel just fine.

I think that's a pretty good determining factor for me, personally...does the pain go away if you warm things up, or does it get worse or stick around. My knees have been like that my whole life...and I don't even consider it pain, just fatigue after hard work.

What one person views as pain another person may not. You know your body, and if something is wrong, consult a doctor, or get a bike fit (or put in some research like you're starting to do now). It probably wouldn't hurt to move your saddle back 1cm and see what happens. You know when I really was able to start dialing in my fit...when I got an indoor trainer. It allows so much time for thinking and tinkering and tweaking. There are some really good cycling coaches out there with blogs...and bike fit is a pretty popular topic for all of them.

Thanks for all the info guys: the pain is right at the front of the knee, so it sounds like i need to raise the saddle some. One other thing is, I'm on a 56 frame and some say that size might be to small for a 6 foot guy. Could this also be an issue?

I doubt that a 56 couldn't be adjusted to be a close enough fit to eliminate that issue. Raise your seat just a hair and "plumb line" your knee/toe alignment for fore and aft on the seat. Make small adjustments, going big can hurt too.

x2...

Thanks guys, i have a 40 mile set for Sunday and will make the adjustment tomorrow...

Read this article about knee pain while cycling ...
CYCLING PERFORMANCE TIPS - Leg, Knee, and Hip Pain

It's from a site called, Cycling Performance Tips:
CYCLING PERFORMANCE TIPS - Main Page