fall sensor

Argh....

What is the rationale behind a fall-sensor?
Does it cut off the starter only, or also fuel pump?

If I made one, it would stop the fuel pump. What Aprilia
did, you should know better then me as you own one.

Is not cutting off fuel at high lean angles dangerous?

On a moving bike that is under any sort of control, yes. But
that is not what fall sensors do. The reason has to do with
physics but I don't feel like trying to explain it right now.

Thanks to centripetal forces, it won't cut the fuel when you're leant over,
it relies on gravity (or acceleration, eg cornering thrust) being straight
down relative to the bike, and will only cut the fuel if the bike's laid
over on its side at an angle to the gravitational forces. You'd have to be
cornering with not just knee down, but hip and elbow too, to make it cut out
while moving...

I spent all day wondering why my 2004 Aprilia RSV1000R did
not start.
I had heard a noise from the fall-sensor, which I thought
was the motion sensor of the alarm. Looked inside, saw
a ring, and concluded that the noise of the loose ring is
normal. After refitting, the starter motor would not work.
It turned out that I had refitted it upside down.

Can't see what use that sensor is.

It lets you know you fell in case you are unaware that you fell.

That can't bee too hard. Imagine the carnage a bike on its
side with the throttle stuck fully open can do to itself and
anyone tangled up with it.

Having gas being pumped out of a hot bike on it's side is a bad thing. Rider
may be unconscious. Bike may be seriously damaged if hit by another vehicle.
Think worse case scenario like your in a ditch and the bike is on top of
you. It's not just incase you drop it in a parking lot.

Ah, OK.
I understand now.

There seems to be an epidemic of people wanting to blame others for their own
mistakes since Gene
Cash disappeared.