> I expect that even if the gyros stop while you're driving you wouldn't fall over because... well because that's how bikes work.
I don't imagine the dynamics would be the same, after all, you're the gyro on a normal bike. If the vehicle was unloaded and you were going straight, you'd probably be able to keep enough manual balance control to come to a relatively controlled halt deploying the parking struts.
However, I imagine the gyros are going to be compensating for internal imbalance (shopping, baggage) in everyday scenarios, or be travelling around a corner, or in traffic, etc, so you might have less time than you think to regain control before toppling.
Don't the wheels themselves act like gyros at medium speed? But I get your point, losing the gyros out of the blue on the highway might create a very dangerous situation.
This is a common misconception about why bikes stay balanced.
Generally the gyroscopic force caused by the spinning wheels is not enough to counteract other forces.
What actually keeps the bike upright is the steering. When you steer the bike slightly left (by pulling the left handlebar), the bike will lean to the right (because of the apparent force caused by inertia). Thus, if you are "falling" on the left side, steering left will bring you back upright.
You normally don't think of it in this terms, partially because once you learn riding a bike it all becomes automatic for you, and partially because the geometry of the bike which causes it to steer in the direction of a lean.
In any case, if you find a way to make it steer in the lean, then it will be self stable.
This is also why you can be stable on a bike at very low speed. The amount of steering becomes very apparent. You might be surprised how long you can stay balanced at extremely low speed if you just allow yourself to change direction.
Yes they do, but the primary reason bicycles (as well as motorbikes) have stability is because of trail - the contact point of the front wheel is behind the steering axis.
A banked-over bicycle naturally tends to turn into the corner because of trail, and that turning-in torques the bike back towards upright - turning the handlebars towards the centre of the curve moves the bottom of the bike towards the centre of the curve, and that pulls the bike upright.
The larger the trail, the more stable the bike is. Sportsbikes tend to have shorter trail so that they turn in faster, cruisers tend to have longer trails so they are more stable on long straight roads.
Loss of gyros would be far more noticeable at low speeds (less than 20mph) than high speeds IMO.
While trail and gyroscopic forces both influence steering and stability, neither are required. It has been shown that a bike can still be self-balancing even without trail or gyroscopic forces, though positive trail and gyroscopic forces do make it easier to balance and more stable (see http://bicycle.tudelft.nl/stablebicycle/StableBicyclev34Revi...).
ithkuil's comment is the more accurate description of what is going on.
ithkuil is saying the same thing as me, in a different way. I'm talking about how bikes are self-stable, he is talking about how bikes are stable with active input. Trail creates a steering feedback system. You need feedback from lean into the steering in order to create something self-stable, and trail is the simplest way of doing that.
People are usually a destabilizing factor on bikes. Very common to see bikes that lose a rider in motorcycle racing to actually continue quite stable on their own.
I don't imagine the dynamics would be the same, after all, you're the gyro on a normal bike. If the vehicle was unloaded and you were going straight, you'd probably be able to keep enough manual balance control to come to a relatively controlled halt deploying the parking struts.
However, I imagine the gyros are going to be compensating for internal imbalance (shopping, baggage) in everyday scenarios, or be travelling around a corner, or in traffic, etc, so you might have less time than you think to regain control before toppling.