It’s the job of the salesman and/or the bike company to make certain bikes seem to the consumer like they are so much faster than others. This very well may be true in some instances, but it is important for you to understand that, ultimately, their sales pitch is just a marketing tactic. No, what will get you the most speed on your road bike is your experience in riding it, as well as how good the condition of the bicycle is in. Speed is mostly determined by the conditions you’re riding the bike in (such as you is if you’re riding with or against the wind, or if you’re going up or downhill), and how strong your legs are.