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Discussion Starter #1
Hi all,

My much loved 2008 848 with 70mm slip on Termis, race ecu ducati has been doing an awful lot of stalling since I had the 12k service done a little while back. s part of the service I changed belts with OEM Ducati belts at the time, used Oleon oils and lubricants, run premium Mobil (Australia) or BP (Australia) 98 RON fuel at all times.

Before posting this thread I did google and take time out to conduct some historical research on older threads and discovered some information but it was a little old and as such I wanted to ask forum members to be patient with me because this topic has been covered elsewhere and spare their thoughts and suggest any possible current fixes that have worked for them.

After my 12k service it ran off and stalled a few times a week and regularly "sneazed" or made a backfire sort of noise in the airbox like it misfired and immediately fired. During colder weather it stalled during start and warm up. Occasionally it stalled when clutch was pulled in and I was coming to a stop. It also would randomly stall at optimum running temperature, so I can't really pin it to any specific condition.

Today I took it to the Ducati Specialist. I had the TPS reset and everything balanced and put on the Dyno to assist in tuning.

At the shop started and ran fine. Leave the shop get a few hundred meters down the road and it does the "sneaze" keep riding on and then 6 times more later it's sneazing more than it was before. It also stalled twice at random times.

Though the bike runs smoother on acceleration and the response has greatly improved after tuning it is worse for stalling and "sneazing then before"

I'm heart broken. I spent 3 hours, travelled 120km round trip, and forked out $300 and it's still doing this shit.

I am taking the bike back to another rspecialist and would like to ask people who have had this issue to advise me on some possible fixes.

This issue is common I know that much, but I love this bike and want to find a solution.

****
 

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Court Jester
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I'm sure others more knowledgeable than me will chime in. Seems like you've done a good amount of trouble shooting. I'm going to take a guess and say something to do with the fuel. Maybe a kink in the fuel line or the fuel pump itself?
 

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The backfiring coming through the intake trumpets and into the airbox, is a very common problem caused by pre detonation, which is why it tends to stall.

Few things… first off, the 848 slip on's shouldn't be 70mm, thats odd. The "BIG" 848 exhaust is 57mm.

Second, have you replaced belts successfully before and what technique did you use to mark the timing before you pulled the belts off?

If before the service you had no problems, then after the service you had issues, its very clear to me, the service was the issue. So we have to re-trace your process during service to discover what went wrong and then remedy it before the issue becomes a bigger problem.
 

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Discussion Starter #4
Hi all,

I'm the third owner of the machine. As far as service history on my bike it's documented in the original books as having completed all recommended scheduled servicing as per updated factory recommendations at time of service.

I did my 12k scheduled service and had belts replaced, valve clearances done and fluids changed and after this period the bike has been running terribly. Prior to this it ran well, with occasional stalling here and there. Having nearly been killed due to the stalling the other week coming out of my street I took it into the shop and it was "tuned" but now it just doesn't run at all.

Starts fine, as soon as it reaches 40 degrees Celsius it stalls. As soon as it is restarted moments later it stalls. Basically I can't even ride it.

I complained to Ducati Australia and have been in regular contact with someone who has arranged for my bike to go in to the main Ducati service centre for assessment.

Problem is a Ducati specialist worked on it previously and i'm not confident that they will fix it and i'm unable to ride it at present it stalls that often it's unsafe.

I'm keen to see if they can find out why it's doing it and have it rectified.

Any ideas? Cam timings maybe? re flashing the ECU timing? it's killing me.
 

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I've written many threads about this, but to condense it…

The bike has shower injectors which spray fuel on top of the throttle plate when at idle. The air/fuel mixture has to travel around the edges of the throttle plate AND/OR through a small hole in the side of the throttle body itself which leads to BELOW the throttle body, bypassing the throttle plate all together. This hole/passageway is controlled by a little brass screw, which increases or decreases the flow rate.

The problem is very simple… the air/fuel mixture isn't perfect at all times with the throttle plate closed, (at idle) its just impossible. Variations in temperature, change the way this system works. Most motorcycles have below throttle body injectors and all that needs to come from above the throttle plate is the air at idle. This way, the fuel atomization is perfect when the throttle plate is closed. Ducati stuck with a single above the throttle body injector and did not use a double injection system like the big 4 do.

Solution? lots and lots of tuning. Most of the issues can be resolved by simply balancing the air screws, balancing the throttle plates and adjusting the fuel mixture at idle. Stock the idle map is all sorts of messed up, mostly due to emissions reasons. You need to yank those stock can's off and get someone to re-map the bike for use without catalytic converters. This will open up the flow of the system and allow better tuning to be performed. You can't run a map with more fuel with the stock exhaust because it will destroy the catalytic converters inside due to potential excess unburned fuel build up.

Cam timing does make a difference, but I'd assume the shop knows how to time these bikes right.
 
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