Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > Supersports: SS / SuperSport / Supersport 950 > Bike Lurching/Surging/Coughing Problem - Help!!

Had similar issues before on a 900SS was an HT cable breaking down under load, finally traced it by spraying water onto leads via a greenfly killer in the garage in the dark and seeing the break down, I know 'how those long winter evenings must fly by', but bl**dy found it eventually !!!

[phillc]

Originally Posted by Jools

Bugggerit...if I'd known they had one of those at the trackday

Yeah, I've just had a little swear too.

My main problem is that I don't have the time to get it to anyone with a diagnostic machine before I'm due to catch the Eurotunnel on Friday evening. So, I'm prepared to try everything I can myself at this stage!

Maybe a diagnostic machine is the only way to go......

[phillc]

Originally Posted by DaveB916

Had similar issues before on a 900SS was an HT cable breaking down under load, finally traced it by spraying water onto leads via a greenfly killer in the garage in the dark and seeing the break down, I know 'how those long winter evenings must fly by', but bl**dy found it eventually !!!

Perhaps I'm being ignorant - very possible - but I don't quite understand. Please excuse me, but what is an "HT cable" and how did spraying water on it in the dark help you to see the break down?

HT cable is cable that goes on spark plug, you can see it arcing to heads or frame depending where the insulation is breaking down, hence it discharges there and no spark at plug = misfire tends to happen under load and more if damp.

[phillc]

Originally Posted by DaveB916

HT cable is cable that goes on spark plug, you can see it arcing to heads or frame depending where the insulation is breaking down, hence it discharges there and no spark at plug = misfire tends to happen under load and more if damp.

OK, great, now I understand. I'll check the insulation around them tomorrow at least. Thank you

I know this may sound bizzare but:

If you can take it for a ride in the dark with the side panels off you will see the arcing very easily if the insulation is breaking down, alternatively as a very short cure bind the HT cables with insulating tape, but the tape will also fail soon if the cable is breaking down.

Also had this happening with a Subaru when under full boost, more difficult to see in the dark tho'.....lol

Cheers

[phillc]

Originally Posted by DaveB916

as a very short cure bind the HT cables with insulating tape, but the tape will also fail soon if the cable is breaking down.
Cheers

If it works for 3 days over the weekend in France, I'll be very grateful. So, I'm going to try this anyway.

[phillc]

Someone has suggested to me that the problem might be the engine temperature sensor on the front cyclinder. They only knew about Monsters but thought Supersports might be the same. Apparently this sensor can be "fiddled" with to run a richer mixture.

Anyone know more about how to do this? Or if indeed it's worth doing?

[phillc]

OK, so I took my bike into the Ducati Proteam and Wimbledon. I needed to get things fixed quickly and I wanted somewhere close to home, so I chose these guys for the first time.

Just been on the phone to them and apparently my "trimmer" was set to -55 which has leaned the mixture right out. They've reset it to -10 (factory setting is 0 I believe) and the bike is running fine.

Can anyone tell me what else a "trimmer" might be called and what it does/how it's set etc???