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Discussion Starter #1
New Ducati owner here,

Been having a weird engine issue recently and am trying to figure out what needs to be repaired. The past couple of rides I've gone on, after about 40-60 minutes of running, if I get on the throttle moderately hard or hard, the engine violently stutters at 7000 rpm. It feels almost identical to running out of gas and firing on and off for brief periods at a time (although does NOT feel like hitting a rev limiter -- the bike seriously goes from totally on to totally off in rapid and random succession). Here is a comprehensive list of observations and symptoms:

-only happens when engine is warm or after prolonged running (past 3 temp bars)
-only happens when bike is in gear. I can rev it up to redline no problem in neutral.
-problem tends to get worse as I ride but eventually goes away completely if I 'baby' the throttle and just cruise at low revs, however the last time this happened the 'rev ceiling' would gradually decrease and the problem eventually started happening at around 4000 rpm
-has died completely before and would not start back up until full ignition cycle (key turned off to on) -- more on this -- one time, the bike died as soon as I put it in gear until I ran it through the whole ignition cycle as well.
-problem is intermittent. Happened the 2nd and 4th times I spiritedly rode it through the canyons. 1st and 3rd times were fine
-happens in every gear
-when the problem happens, BOTH cylinders do not fire. It never just runs on one cylinder
-revs will go up 'if forced', only after significant stuttering and only if the bike doesn't completely die, which it has before.

-spark plugs look good and practically identical
-air filter is clean
-no warning lights
-doesn't overheat
-tends to happen right after re-filling my gas tank
-running 89 octane as per manual specification (USA)
-I have a leaky clutch slave cylinder that is slowly dripping onto the kickstand kill switch (don't worry, this has since been fixed).
-model year 2009 with 12k miles and according to official service records, full service done at 7500 (although for some reason the engine wrench symbol is still on my dash?)
-bike is totally stock

My own analysis:
I've read that this issue could be caused by anything from a bad fuel pump, fuel filter, air filter, spark plugs, spark plug leads, ignition coils, exhaust butterfly valve, bad ECU, or even the damn kickstand killswitch.

1. I'm pretty sure it's not the spark plugs. Could be the leads and coils since the problem only happens when the bike gets warm and both assemblies are right above the front cylinder, but then again, I feel like it would be awfully unlikely that BOTH sets of coils and leads would be failing simultaneously. The engine dies completely and turns back on completely, no one cylinder firing nonsense going on.

2. Kickstand killswitch is a real possibility considering that they get dirty easily and tend to be problematic in general. Also, problem only tends to happen in gear...very suspicious... Only reason I'm having a hard time believing that it really is the kickstand killswitch is because this issue only happens when the bike is warm, and the switch is well out of the way of any significantly hot engine component.

3. I haven't checked the fuel filter because I haven't managed to drain the tank yet. I really, really hope it's something as simple as a dirty filter. Although, are fuel filters affected by heat or prolonged running? I'm going to tear into the tank again today and report back.

4. Fuel pump seems to be working fine. Primes every time. Affected by heat?

5. Don't see why it would be the exhaust butterfly valve...I don't feel like the engine would cut out completely and so abruptly if this were in fact the issue. Also, I still have the stock exhaust system on the bike.

6. I've read that a bad ECU is rarer than a blue moon. Would like to hear from any Monster owners who have had issues with it though.

TL;DR: intermittent fueling issue is causing my bike to stutter and hesitate abruptly at 7000ish RPMs under load and generally gets worse under hard acceleration.

So. Any ideas? Thanks!

3 Posts
Discussion Starter #2
I believe I've figured out the issue. Did a deep clean of the kickstand killswitch and the problem has not come back after 2 long rides through the twisties.
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