Yes I'm a newbie. But Id rather be informed than sit around and do something wrong. Anyways, my question is this:

I am currently working out 4 times a week. 2 days on, 2 days off in hope of gaining some serious mass. I am begining to think that I am working too hard and not giving myself enough time inbetween workouts to recoup/gain weight.
Problem is, I am addicted to hitting the gym every other day and I feel like I might lose motivation if I stop going so frequently. I was thinking of going every other day to ride a bike for 10-15 minutes. My concern is that, will riding a bike a few times a week slim me down and hurt my weight gain? My legs are pretty lanky as is, and im not sure if the bike will build make my legs bigger or smaller.

Thanks in advance,
Frank