Originally Posted by 46x17
Yes gears will make you go faster for sure. That is why the TDF involves gears these days.
However, your post was talking about brakes vs. no brakes (your drive train still is one though) and that was the point I was talking too. I believe the same fixed wheel bicycle (no gears on those remember) can be ridden as fast with a handbrake as it can without a handbrake by the same skilled rider.
The rear brake of a bicycle, applying forces that are LESS than those required to cause the tire to lose adhesion, will cause a bike to decellerate at a rate that is SIGNIFICANTLY slower than that caused by a front brake that is applied to the same degree (tire maintaining adhesion, bike not flipping). Car brakes work the same way.
Obviously, the drivetrain is capable of producing the same speeds no matter how many brakes you have, but it is PHYSICALLY IMPOSSIBLE to stop ANY VEHICLE as fast with just rear brakes as one can with both front and rear. IT JUST DOESN'T WORK!
If you don't believe me, ask an expert! Jobst Brandt, Sheldon Brown, David Gordon Wilson, your physics professor, whoever!