Hi

I'm having a bit of bother after rewiring my indy, it has a 98 cbr919 engine

just took it for a test drive and it seems ok, until i put my foot.

it pulls nicely up to 8.5-9k rpm then suddenly the engine cuts out, tacho goes to 0rpm, i dip the clutch, get a huge backfire and then it runs again (if its below 8.5k rpm)

can anyone give me an idea whats causing this or where to start looking?

im pretty sure its something to do with the wiring

cheers

ECU loosing sync with the engine, once it gets too fast the ecu doesn't know where the rotation of the engine is so it stops spark, unburnt fuel fills the exhaust, once the revs drop the ecu re-syncs, starts sparks and you get your backfire.

Check wiring around the crank position sensor/cam position

crank position sensor? does it have one?
would what your saying cause the tacho to drop off too?

as far as i know the only sensor as such is the throttle position sensor

its a 1997/98 engine

also, it does it underload and just sat on the drive (though at slightly lower rpm when sat still)

Well I would have thought that it had a CDI and would have a crank position sensor. My 1998 zx9 has one. Unless it has a distributor it has to have one

It has a crank sensor under a small cover above the generator from memory

from the drawing in my haynes, im assuming its the pulse generator that is the 'crank position sensor'?

would this cause the tacho to drop off too?

i was so excited when i took it for a test drive and everything worked then i got on the open road and almost cried
literally sick of working on this damn car now

this is the nearest drawing i can find online to the one im working from

http://i2.photobucket.com/albums/y45/norcal2500hd/96-97-wiring-diagram-900rr.jpg

yes if you loose crank position then tacho will drop off, usually on the right side of the crank if sitting on the bike

Ok, I'll check it's plugged in and the wires go to something

turns out it i hadnt earthed the green and green/white cables from the CDI, problem solved