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Discussion Starter · #1 ·
Sometimes as im riding, my bike will do a weird hiccup. Its almost as if i let off the throttle for a split second (but in actuality, the throttle is steadily cranked). This used to only happen in 1st and maybe 2nd gear at lower rpms.

I don't know if I'm describing this properly. But the bike will be moving along steadily, and then do like a slight jerk/hiccup, and then just continue along its way.

its a 2002 Monster Dark 750 ie and i just passed 6500 miles on it. I recently checked the belts just to make sure they were in proper shape, and not a single fray. so that made me happy. I really baby my bike, so this little glitch (if it is even a glitch) is making me nervous.

I didn't get the 6000 mile service yet. I plan on doing that soon. I was wondering if maybe this may have something to do with the valves? I have no idea what it could be.

any ideas?

thanks!

-derin
 

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I've had that problem before on FI bikes. Sometimes tuning will take care of it and sometimes it won't.
 

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The bike is over 8 years old and it only has 6,500 miles on it. Get it serviced, tuned up, and ride it a lot more. That will take care of it.
 

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my 07 695 did that sometimes, usually when rolling of the throttle at low speeds, plenty of UK Monster owners have had this, for me it was no big deal.
 

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Discussion Starter · #5 ·
yeah, thats how it used to happen for me too. it would hiccup and almost make a clucking sound in 1st or 2nd gear at low speeds. but it started happening at higher speeds as well. just wondering what it could be and if having the 6,000mi service will take care of it. Also, the guys at the ducati shop are telling me i should get new belts even though i checked the belts and they aren't frayed at all and seem to be pretty tight. hmm...
 

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It's nothing to do with the belts, more likely the petrol/air mix, with mine it wouldn't happen for ages then I would get a few hiccups then it would stop again. It may well be the lamda sensors in the exhausts, if it is happening all the time get them to check the air mix and sensors, in a way it seems to be part of the 695's character.
 

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There are several threads on this subject...

The short of it is your timing is slightly off, you need a tune up and new belts. Once you do that service the bike will run cooler and without spitback. It's lame as hell they are coming out of the factory Like that and even lamer the shops all pretend it's the first time they have heard of such a thing. But that is the way they are and that's the way it is. If I didn't love my bike so much I'd flip on them for giving me a bike that ran like crap right from the factory then playing dumb until it was reasonable to hit me up for the service.
 

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I found this letter from a race mechanic, after I wrote him about the same spitback issue and asked about getting a full termi system, since others told me it would help:


O2 sensor based closed loop operation is a bad idea. You probably already know this, since you were suggesting going to a DP ECU. The problem is of course that a piggyback device
like a Power Commander cannot affect the area where the stock ECU is in closed
loop operation (it will always try to “correct” whatever you do).
*
On a Ducati, closed loop is an
even bigger problem than with other engines, and that’s because of the
desmodromic valve actuation. *The
closing rocker does close the valve, but even though there is a clothespin
helper spring, the valve doesn’t close as hard as with a standard valve spring
(otherwise mechanical interference would spell out broken parts or high rates
of wear). What this means is that the valves don’t always seal completely when
they close. The head casting stress relieving during the first few thousand
miles of use can exacerbate this problem. Valve guides can move relative to
valve seats (or vise versa), which means that one or more valves may not strike
the seat(s) squarely anymore. However, for the reasons already mentioned, even freshly
cut valve seats and lapped valve faces may not provide perfect sealing every
revolution. If the exhaust valves leak, the O2 content in the exhaust pipe will
go up. When the O2 content goes up, the ECU thinks there is a lean condition,
and adds fuel. Obviously adding fuel will not reduce an O2 content that is
caused by leaky exhaust valves, so the ECU keeps merrily adding fuel until
there is a rich misfire. When there is a rich misfire, the O2 content goes up
even higher, causing the ECU to add even more fuel. The only limiter to this
nonsense is either that the engine will stall, or that the ECU has a point
programmed beyond which it will just not add any more fuel. In my experience,
extremely poor running to the point of stalling is not out of the question.
*
I recommend the following:
*
Take all of the opening shims out
and perform a leakdown test to see if a valve job would be prudent.
Depending on the results and your
inclination, cut the seats and lap the valve faces.
Adjust the valves.
Tension the belts.
Time the cams.
Clean, pattern test, flow test,
and match the fuel injectors.
Install an ECU that does not use
closed loop operation.
Develop custom fuel and ignition
maps on the dyno.
*
Notes on the above:
*
Ducati has been trying to sell
more bikes by offering cheaper maintenance costs. The problem is that the
quality of the maintenance has gone down as a result. Belt tension affects cam
timing, whenever the belts are tensioned, the cams must be timed. They used to
do this properly with a degree wheel and dial indicators. Now they have some
holes in the head and cams where you insert a pin to align them. The crank is
held in place with a locking tool. With everything held in place like this, you
tighten the pulleys on the cams and that’s it. The problem is that this method
is far from being accurate, and poor performance is the result. In fact, no
Ducati that has ever come in here has had the cams timed correctly. To add to
the problem, the cams are usually not ground to the factory specifications in the
manual, and the fronts are often different than the rears. By degreeing the
cams with a dial indicators and a degree wheel, conscious choices can be made
about how to deal with whatever discrepancies. This is the only way to get it
right, but is of course quite a bit more labor intensive.
*
Prefab fuel and ignition maps
always leave something to be desired. For this reason, I don’t recommend the DP
ECU or reflashing the stock ECU to DP specs. A Power Commander would work if
there were a way to eliminate closed loop, so a DP ECU with a Power Commander
would work. However, a fully programmable ECU is really the way to go, and that’s
what I recommend. That way we can eliminate closed loop and improve the maps to
address symptoms or develop complete custom maps from the get go. It’s also
cheaper than the DP ECU/PCIIIUSB combo, eliminates the use of a piggyback device
which adds a point of failure, allows programming of the ignition maps and
various other parameters such as cold start enrichment, rev limit, etc., and
adds the ability to plug in other devices, such as a shift light, quick
shifter, etc.
 
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