Flat plane crank

[xain]

Hi all,
I know it's only the AJPs that have flat plane cranks, but I'm just curious about why they're supposedly better for racing.

Also, do they have some wierd firing order, like on Ducattis where there are two firings, then a long pause, then two firings (apparently to improve the impulse recovery in the tyres). Do 4 cyls fire at once, followed by the other 4 or some such?

I know these beasts have a different exhaust note to the Rover unit, and I wondered what was actually going on in them.

Cheers
Jon

[xain]

Ah, so the idea is to combine 2 exhaust pulses so that while they are travelling down the exhaust system they effectively siphon more mixture into a cylinder that is just starting it's intake phase with the exhaust valve still open (overlap)?

So I guess the slightly different sounds inthe exhaust nbote are caused by two cylinders firing at once with a *tiny* difference in times.