Strange......Bike is running the 924cc pistons and 54mm full termi. Been to dyno and she was running sweet as a nut. Fitted HM lever quick shifter and speedo healer to her at the same time. Go for a nice run out to test I thought.. First 1/4 mile up the road, shifting sweet as up the box..I rolled off and BOOM, (were talking double barrel shotgun, not your average exhaust popping) BOOM, BOOM...engine cuts... Started up and turn around, same thing on the way back. Doing it stationary with a throttle blip ...So, I removed the QS tried again, same deal, filled her up with fresh fuel, same deal..(new fuel filter months ago as was fresh plugs - new coils 18months ago). Removed the Speedo healer, try again, same deal.....I am thinking the QS operation may have tipped a coil over the edge..It was too coincidental with the fitment of the HM QS... Any thought or experiences? Throttle body air bleed plugs are installed. No air leaks I can find.... tuppence for your thoughts..?
If not QS settings. Possible lean running. You say bike was on Dyno. Was this for tuning or just power runs? If not tuning, what ECUmap are you running?
thx for all the replies, nothing else done but fitting the QS and Speedo healer at the same time, then the problem. She was running beautifully after the dyno with a lightly modded 999S map. 14afr on full pull dynojet dyno. just a month or so ago. ...the only connectors disturbed were the wheel speed sensor and both coil packs. I've rechecked those and still the same..lot of cash to try two new coils again, replacements were new Beru's.
All refitted stock, the HM QS loom has a short and long coil pack loom that only fitted in the front and rear positions, they can't be transposed.. Thx though for the thoughts. Any elec checks I could do on the coils?
Gona get a fuel pump relay today and see if it makes a diff. Wheres the best place to get reasonably priced new coils?
eBay, or Amazon. Better still, research whether any cars use the same one and search suppliers for those..
Bought another fuel pump relay but it appears as a fault 16.0 on startup. The relay has a diode built in. I assume the bike doesnt like it...
New relay fitted, still the same. Bike warms up and runs perfect up till roughly 50c coolant temp, them Boom! on the overrun, bike stationary..Any other ideas? Coils are next but expensive trial fix....
@David Rae take a look at this https://www.ducatiforum.co.uk/threads/998s-refurb.78243/page-6 go from post #120 bottom of page 6. I had a similar sounding misfire problem which turned out to be a loose connector to the horizontal injector. It was on the white/violet cable (on the 998 wiring diagram) which feeds first the horizontal then the vertical. If suce read the wiring diagram correctly the injectors are wired in series not parallel, if the first connection is broken they’re both out of action. It’s worth a check anyway. I don’t know on the 749 but the 998 has shower injectors so it was easy enough to lift the tank and check whether they were squirting fuel or not. Hope this helps
Thanks very much Paul, I'll take a look at that. The injector arrangement is shower, wiring is identical to your description. Thanks for your reply. I just cant get over the coincidence that it only occurred first run out after fitting the HM QS..I'll lift the tank at have a look at the injector plugs/loom this morning..
