Ducati Monster Forum

Moto Board => Tech => Topic started by: Jdan on April 18, 2011, 03:04:20 PM

Title: Intermittent loss of power.
Post by: Jdan on April 18, 2011, 03:04:20 PM
Hey guys. I feel like I'm always asking you all some sort of question for my bike but here goes.

My 2000 m750 has just started to intermittently lose power while riding. Occasionally while riding, it feels like someone sucked out alot of the the power. Throttle response will be very delayed, there is lots of vibration, and acceleration is extremely slow. The bike will stay this way for about a mile or so, and then everything just seems to return to normal. I went out today and it happened twice.

I'm asking because I have a long trip planned for this thursday, and I don't want to be broken down on the side of the Jersey Turnpike because my problem is larger than it seems to be.

Any ideas?
Title: Re: Intermittent loss of power.
Post by: ducpainter on April 18, 2011, 03:15:35 PM
Almost sounds like a cylinder is cutting out.

You were having fueling issues. Have you checked your plugs?
Title: Re: Intermittent loss of power.
Post by: Jdan on April 18, 2011, 04:07:11 PM
I checked all the plugs on the side of the road. Everything looked fine but I'm gonna do a more thorough search later.
Title: Re: Intermittent loss of power.
Post by: Munch on April 19, 2011, 02:28:32 PM
Check your ground wire also...
Title: Re: Intermittent loss of power.
Post by: Jdan on April 20, 2011, 03:31:35 PM
It was the spark plugs. Both were dirty and one had a sloppy connection. All fixed  [thumbsup]

Thanks for the help! Cheers.
Title: Re: Intermittent loss of power.
Post by: desmodoktor on April 21, 2011, 05:49:06 PM
Quote from: Wilco on April 20, 2011, 03:31:35 PM
It was the spark plugs. Both were dirty and one had a sloppy connection. All fixed  [thumbsup]

Thanks for the help! Cheers.

i had the same problem on palisades pkwy :D
one of the spark plugs is dirty.. what do u mean by sloppy connection?
did your bike backfire a lot when you started loosing power?
what did u exactly do ? did u have backfire from the intake?
Title: Re: Intermittent loss of power.
Post by: Jdan on April 21, 2011, 07:40:44 PM
Yeah. Lots and lots of backfire. By sloppy connection i meant it's going bad and doesnt always fire.
Title: Re: Intermittent loss of power.
Post by: Jdan on April 23, 2011, 04:44:39 PM
Gotta revive the thread. Spark plug change seemed to fix the problem, but it's returned!  :(

Went for a ride today and about 15 miles in the loss of power returned. I noticed this time that the lack of acceleration only begins to happen during engine breaking or when the bike is in a low rpm range. It can be fixed by clutching in, WOT, and clutching out, but as the bike decelerates again, it returns.

My only ideas are that the carbs are not synced together, a needle-float issue, something with the throttle bodies, ?another fuel delivery issue?

Any ideas? This one is really killing me.
Title: Re: Intermittent loss of power.
Post by: ducpainter on April 23, 2011, 04:46:04 PM
pull the plugs and post pictures.

Is that possible?
Title: Re: Intermittent loss of power.
Post by: Jdan on April 23, 2011, 05:42:24 PM
Spark plugs are brand new NGK's bought yesterday and gapped to .65mm.

Them together
(http://i.imgur.com/W04Oc.jpg)

Closeup of number 1
(http://imgur.com/wVMaN)

Closeup of number 2
(http://imgur.com/yJ1oq)
Title: Re: Intermittent loss of power.
Post by: ducpainter on April 23, 2011, 05:57:31 PM
Is #1 from the horizontal cylinder? Looks gas fouled to me.

I know you have a ca-cycle track tank.

Have you removed all the extra vacuum lines?

Have you set things up?

Synch, float level...etc?
Title: Re: Intermittent loss of power.
Post by: Jdan on April 23, 2011, 06:18:55 PM
Extra vacuum lines are removed. I did not know that the synch and floats need to be set up for the new tank. Everything has worked fine on the bike until now. Tank was installed ~400 miles ago
Title: Re: Intermittent loss of power.
Post by: ducpainter on April 23, 2011, 06:26:25 PM
Quote from: Wilco on April 23, 2011, 06:18:55 PM
Extra vacuum lines are removed. I did not know that the synch and floats need to be set up for the new tank. Everything has worked fine on the bike until now. Tank was installed ~400 miles ago
Shouldn't have to be reset because of the tank, but you've been having trouble ever since.

Something happened.
Title: Re: Intermittent loss of power.
Post by: Jdan on April 23, 2011, 10:46:45 PM
I guess it's to the shop again. I'll give you guys an update soon
Title: Re: Intermittent loss of power.
Post by: desmodoktor on April 24, 2011, 05:49:03 AM
Quote from: Wilco on April 23, 2011, 04:44:39 PM
Gotta revive the thread. Spark plug change seemed to fix the problem, but it's returned!  :(

Went for a ride today and about 15 miles in the loss of power returned. I noticed this time that the lack of acceleration only begins to happen during engine breaking or when the bike is in a low rpm range. It can be fixed by clutching in, WOT, and clutching out, but as the bike decelerates again, it returns.

My only ideas are that the carbs are not synced together, a needle-float issue, something with the throttle bodies, ?another fuel delivery issue?

Any ideas? This one is really killing me.


i have 100% exactly the same problem! every single word you said!
today ill build up a manometer to sync the throttle bodies.
my spark plugs look exactly the same .. the one from the horizontal cylinder is black and wet..
i was thinking to change the coils but idk.. let us know when you get your bike plz.
Title: Re: Intermittent loss of power.
Post by: Jdan on April 24, 2011, 05:58:21 AM
QuoteShouldn't have to be reset because of the tank, but you've been having trouble ever since.

Something happened.

Well the first time I experienced it, I had just run over a killer pothole. Something must of come loose.
Title: Re: Intermittent loss of power.
Post by: Jdan on April 24, 2011, 06:19:14 AM
It's most likely something with the fuel delivery. Everytime it happens, the carb overflow tube is spitting gas all over the road.
Title: Re: Intermittent loss of power.
Post by: ducpainter on April 24, 2011, 06:20:46 AM
Quote from: Wilco on April 24, 2011, 06:19:14 AM
It's most likely something with the fuel delivery. Everytime it happens, the carb overflow tube is spitting gas all over the road.
then take that float bowl off and clean the needle and set the float level.

the extra gas is fouling the plug.
Title: Re: Intermittent loss of power.
Post by: Jdan on April 24, 2011, 05:46:07 PM
Quotethen take that float bowl off and clean the needle and set the float level.

the extra gas is fouling the plug.

Yep. Going to do a full carb reclean but the bike is 400 miles away until i finish this semester.