Long have I wondered about the gyroscopic impact of the bicycle's wheels.

I firmly believe that the wheels on a bike act as gyroscopes. And, the heavier the gyroscope, the greater the gyroscopic effect. The further the weight is away from the rotational center, the greater the gyroscopic effect. Remember, this is just a theory I have long held and I welcome the opportunity to discuss it.

Pick up a front wheel you know to be true. With no tire or tube mounted, give the wheel a good spin, hold the wheel by the axle ends and you will immediately feel the gyroscope at work. As you try to tip the wheel from side to side, while the wheel is spinning, you will feel it want to resist any form of lateral movement.

Now, install a tube and tire. Repeat the above test and, in your mind, try to compare the feel to an unclad rim. I feel a distinct difference, in the amount of resistance imparted, by the addition of the tire and tube. The wheel, with tire and tube mounted, will offer resist movement, from side to side, more than the unclad example.

Translate that phenomenon to the bicycle and think about what two gyroscopes, working together, will do to the feel of the bike. The bike will feel more stable, marginally so, to be sure, but different, none the less.

With that in mind, it seems possible that the increase in the gyroscopic impact will manifest itself as increased stability, hence making the no hands thing seem better.

A bicycle, standing still, will fall over immediately. A bicycle, rolling down a hill, sans rider, will fall over eventually.

Now keep in mind, this is just my theory and I could well be wrong. But think about it.

So, the differences between 27 and 700 wheels are many and each factor, (tire pressure, wheel diameter, rotational weight, rotational speed and other things mentioned in this thread) must be taken into account.

And Lance Armstrong has considered them all. He goes with 700c wheels every time, does he not? That might be a clue right there.

I probably should just keep my mouth shut, but I would like to hear what others have to say about my theory.