[Diy_efi] Confused! Lost!

[Adam Wade]

Here's one for the experts...  Because it sure has
stymied me.

Kawasaki ZX-12R motorcycle.  Approx. 13 ohm injectors,
so it's a sat driver, right?

Welllll...  The idle trace from any of the injectors
shows what very much appears to be a P&H trace...  A
drop, then TWO spikes in close succession.  Like this:

http://www.easttraining.com/images/Waveforms/gm_tbiv_p&h01.jpg

This is somewhat irregular...  About 80% of the idle
events looks like p&h, the remainder look like regular
sat events, thusly:

http://www.easttraining.com/images/Waveforms/efi_conv.jpg

As the revs come up, the injector events pretty much
all appear to be sat-type.

WHAT ON EARTH gives?!  I was very much under the
impression that driving a high-impedance injector with
a P&H driver would result in the injector acting as if
it was being driven by a sat driver.

Can anyone shed any insight on this?  As much as I
would love to offer the driver schematic, that is
beyond my means; it's a proprietary design for
Kawasaki, although I am led to understand by Kawasaki
technical that they are using smaller engines with an
ECU of the same design.  I am aware, though, that this
does not preclude them from changing the driver
circuit on one model.

For reference, the bike is producing about 175 bhp at
the crank at 10,500 rpm...  Which should mean
something on the order of 22 lb/hr. for each injector.
 Idle is around 1200 rpm.

Is there some kind of trickery going on to help
control idle injection events?  Any insight welcome!

=====
| Adam Wade                       1990 Kwak Zephyr 550 (Daphne) |
|   http://y42.photos.yahoo.com/bc/espresso_doppio/lst?.dir=/   |
| "It was like an emergency ward after a great catastrophe; it  |
|   didn't matter what race or class the victims belonged to.   |
|  They were all given the same miracle drug, which was coffee. |
|   The catastrophe in this case, of course, was that the sun   |
|     had come up again."                    -Kurt Vonnegut     |

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