Originally Posted by pj7

Yesterday, between getting off my first job and going on to my second I had a few hours and decided to go on a bike ride down the cycle path close to my house. I was able to maintain a speed between 9 and 11 mph with bursts up to 16 or 17 mph after taking a breather and cruising at around 7 or 8 mph for a minute or two.
But the whole time I was getting blown away by these guys on road bikes, they must have been going 20+mph, easy, maybe even 30 at some point. I met up with a few of them at an intersection and they seemed to take off like bats out of hell with ease. My estimate is that it only took them 8-10 seconds to reach 20mph without even breaking a sweat, seated the whole time.
Is their conditioning that much greater than mine?
These guys were thin fellas, probably no more than 160lbs and were riding some decent road bikes. I'm at 315lbs now, down from 330lbs (woohoo) and I ride a Hybrid, a Trek 7100. As my conditioning improves is it plausible that I might start seeing speeds like this on my current rig? And what if I were to get a road bike tonight, (not saying I can, but what if) would I see a signifigant improvement on my speed? Is there anything I can do right now to start gaining more average speed?
The reason I'm asking is that I'll be commuting soon, 11 miles each way if I take the bad routes and about 14-15 miles each way if I take a safer route and am wanting every edge I can get.