Thanks Pete - my street is too well lit to do the total dark thing so have tried substitution of new ignition coils. No joy, the bike remains as-is, still the remainder of a nasty vibration after riding for a few minutes.
My thinking is now either:
1) Mains bearings getting loose with time and mileage (I'm really hoping against that) or,
2) Crank position sensor is getting a bit tired and not working 100% any more.
It's an inductive type. The crank position sensor doesn't run on the crankshaft or flywheel, it runs on the half-speed timing gear driving the belts running to the cylinder heads. Initial triggering is via a cut-out spanning two gear teeth, then the sensor counts gear teeth to establish crankshaft position after that.
I haven't yet checked the air gap, specified as 0.6 to 0.8 mm, but this is very unlikely to have changed over time. The Ducati workshop manual doesn't specify coil resistance, I got 660 ohms at the ECU connector but have no new one to compare to or any reliable info from the internet. I have just tried running a timing test using a timing gun and this appeared to show a problem: couldn't find the timing marks either at idle or revving. Unfortunately it's difficult to read these (or not) clearly, after a few seconds of operation there is a steady flow of engine oil over the inside of the timing window glass and it starts becoming very difficult to see the flywheel clearly.
The timing gun is suspect. It's a cheapie:
https://www.supercheapauto.co.nz/p/t...ight/9702.html
Works OK at idle and low revs but has a habit of dropping out once the engine is revved a bit.
So, question for everyone: can these sensors get a bit sick and become walking wounded? Or when they go, they go and that's it, the engine won't run at all? Or is my testing at fault here and there's nothing proved wrong with the sensor yet?
Neels, I've had a think about your bike's running rich at idle problem and the only idea I've got is blocked air bypass jets in the throttle bodies. These are only dominant at closed throttle, ie idle. There's a lot of other things it might be of course but if memory serves it should be possible to completely remove the bypass screws from either side and clean the needle valve seat area via cotton bud and white spirits, without taking anything else apart except for removing fairings. Doing this might mean having to go through the set-up procedure on the throttle bodies though.
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