Originally Posted by
nerdbot5000
Get fit by a bike shop that knows what they are doing, keep your wheels at a good psi, and keep your chain clean. Clipless pedals are a worthy upgrade. Depending on your type of riding, getting lighter wheels for easier acceleration might barely improve your times.
+1
Wheels are the easiest place for manufacturers to go cheap. Thinner racing tires will also help. You'll take them up to higher psi and probably get a few extra flats. Don't try skidding too much on those. You'll understand why when you pay for them.
There are three main key to remember. The first is to improve the engine (you). The second is weight (yours and the bike's). The third is rigidity. It won't matter as much as the others and it will make your bike less comfortable, but a super ridged bike will more directly transfer your energy into speed.