You have only been riding 3-4 months... and you can average 16 MPH? With hills? You are doing GOOD for someone new to cycling!

It has taken me about 800 miles logged on my bike (since October 2004) to get to the point where I can average around 15-17 MPH.

I have learned that to get faster... I had to learn how to spin... and I had to just keep riding. More time in the saddle = improvement.

I had about 2 months where I had to take a step back from cycling as much, and as hard... because of some knee issues... so I had to slow down... and learn how to spin. I can't believe how much better I have gotten because of it!

So, give yourself some time... but you are doing really great as it is!