[ranger_mitch]

I just bought my first bike––a 2000 Ducati Monster 750 Dark––and after a few days of very light riding, I can't get it started. Even when it did start before, it was rough for the first 10 minutes or so and then seemed to warm up.

I can hear it trying to start (the starter seems to be working), but it never "catches" and actually starts running/idling. (There is no explosion). Oddly enough as well, the headlight never goes out when trying to start, only dims.

I fear the issue is carburetor-related, but I have tried to test out all the simpler solutions first.

Here are the paths of inquiry I've followed so far:

• I replaced the old battery today and verified that it was fully charged with a Noco Genius 5 battery charger before testing it out in the bike.
• I took a look at every electrical connection I could find and didn't spot any that appeared loose or poorly connected. One thing of note after reading some other threads on the topic however––I don't hear any relay click when I move the side stand up and down. This shouldn't be the root cause though, as I have started the bike several times leading up to the past 36 hours of not being able to.
• I pulled both spark plugs one at a time and noticed that they were both dark/sooty and a bit wet at the end––seems it may be running rich or maybe I gave it too much throttle while trying to start it. Either way, I held each of them against the outside of the cylinder in my dark garage and verified that they are each getting a spark. I tried replacing them with a fresh set of spark plugs, but while they said they were an exact match for my bike online, the new ones seem too big at the exposed end for my spark plug wires.
• The day I got the bike, I drained the tank and treated with SeaFoam in the fresh gas to try and clean out any rot that may have been in there before. The bike currently has around a half-tank of premium with SeaFoam in it.
• The previous owner mentioned that he had some screw on the carburetors that he adjusted for running in the summer vs winter and that it was currently set for warm temps. I saw one screw between the carburetors that seemeed to match his description and have tried starting the bike after giving it a quarter- to half-turn in each direction. No luck, so I returned it to where it was when I got the bike.

I am just dying to ride this beautiful machine and it's killing me that I can't even get it started. What would you do if you were in my shoes?? Thanks!

 

[m.j.bower.69]

I ride a 2001 M750 and whn I got it the first thing I did was pull the cars and give them a clean in the ultrasonic cleaner. Unless the PO was a keen home mechanic, it's unlikely they've been properly cleaned.
I had hard starting issues that were sorted this way. It's a pain, but at least you'll know they're right. You might want to put a rebuild kit in if they're stock.

Sent from my H4133 using Tapatalk

 

[ranger_mitch]

I should have mentioned this—the PO is a mechanic (owns his own shop) and did a valve adjustment 1,100 miles ago (19,000 miles on the bike)

 

[ediowa]

Did you suspect the fuel was bad? Did the fuel smell like varnish? Had the bike sat for a long time? If yes then I also suspect the carbs will need cleaned.

 

[Bushyeyed1]

What’s the plugs look like? Is there spark?

 

[ronski]

As for the spark plugs, some come with an end cap which can be easily unscrewed, leaving a threaded end which the leads will fit on. just use pliers or grips to unscrew this cap.

I remember my old M900 with carbs. Sometimes a different method is needed for starting. Too much prolonged choke will make it very rich,
Try this, first attempt, choke on half...no throttle. standard these days with EFI etc.
second attempt, NO choke, and a little throttle, Third attempt, No choke and progressively more throttle.
Then back to the choke method.

But then, it's always warm or damn hot here in Perth, so a lot of choke is never needed.

 

[bsasteve]

I just bought my first bike––a 2000 Ducati Monster 750 Dark––and after a few days of very light riding, I can't get it started. Even when it did start before, it was rough for the first 10 minutes or so and then seemed to warm up.

I can hear it trying to start (the starter seems to be working), but it never "catches" and actually starts running/idling. (There is no explosion). Oddly enough as well, the headlight never goes out when trying to start, only dims.

I fear the issue is carburetor-related, but I have tried to test out all the simpler solutions first.

Here are the paths of inquiry I've followed so far:

• I replaced the old battery today and verified that it was fully charged with a Noco Genius 5 battery charger before testing it out in the bike.
• I took a look at every electrical connection I could find and didn't spot any that appeared loose or poorly connected. One thing of note after reading some other threads on the topic however––I don't hear any relay click when I move the side stand up and down. This shouldn't be the root cause though, as I have started the bike several times leading up to the past 36 hours of not being able to.
• I pulled both spark plugs one at a time and noticed that they were both dark/sooty and a bit wet at the end––seems it may be running rich or maybe I gave it too much throttle while trying to start it. Either way, I held each of them against the outside of the cylinder in my dark garage and verified that they are each getting a spark. I tried replacing them with a fresh set of spark plugs, but while they said they were an exact match for my bike online, the new ones seem too big at the exposed end for my spark plug wires.
• The day I got the bike, I drained the tank and treated with SeaFoam in the fresh gas to try and clean out any rot that may have been in there before. The bike currently has around a half-tank of premium with SeaFoam in it.
• The previous owner mentioned that he had some screw on the carburetors that he adjusted for running in the summer vs winter and that it was currently set for warm temps. I saw one screw between the carburetors that seemeed to match his description and have tried starting the bike after giving it a quarter- to half-turn in each direction. No luck, so I returned it to where it was when I got the bike.

I am just dying to ride this beautiful machine and it's killing me that I can't even get it started. What would you do if you were in my shoes?? Thanks!

First up could drain the fuel in carbs and also in tank if can do easily and replace.
new spark plugs have a small nut on top to fit two types of plug caps, unscrew this and you will expose thread and this will fit your caps
Unlikely climate changed since you bought bike so don't fiddle with carb screws and adjustments yet, but if a lot of muck in tank, check fuel filter, pump, and last may likely have to clean the carbies and may be better to give to someone else to do if you are not confident of noting all settings (where screws are etc) putting all back together, and readjust. You may need to get a carbie kit also for the rebuild, about $45. May cost a bit for bike shop to do.
It appears you have spark so likely fuel delivery issue and perhaps a bit of water in fuel, so should should check if fuel is getting through system. The fuel tap works on vacuum as also fuel pump, when motor turning over. Are carbs full of fuel?
Try looking at old monster forum posts and get a diagram of the fuel system

Monster 750 2000 Monster Ducati motorcycle # DUCATI Online Genuine Spare Parts Catalog

www.bike-parts-ducati.com

Good luck

 

[elijahsummo]

Definitely the carbs, I have no doubt. Take em apart make sure theyre good and clean then adjust properly.

 

[ranger_mitch]

UPDATE - It's running again!

Thanks so much to you all for taking the time to write responses to this.

The bike started right up and this is what it took:

• Put in a new, freshly charged battery
• Swapped out the spark plugs (you all were correct that those "too-large" tips just come off with a set of pliers)
• Added some more gas (I find that occasionally, under half a tank, I need to give the bike a little (3 inches or so) shove forward while I'm pressing the starter to get it to go)
• Built my own understanding of the fast-idle device (the round "switch" on the left handlebar that works a bit like a choke when the engine is cold

 

[ranger_mitch]

What’s the plugs look like? Is there spark?

The plugs were fairly soot-covered at the tip (probably indicating a rich mixture), but I checked them individually and both had a reasonably strong spark. I went ahead and replaced them while I was in there because it's cheap and easy peace of mind.

 

[ranger_mitch]

Did you suspect the fuel was bad? Did the fuel smell like varnish? Had the bike sat for a long time? If yes then I also suspect the carbs will need cleaned.

The fuel was likely bad, as it came from a can in the previous owner's garage and I don't know how long it had been in there. I drained that fuel as soon as I got it home and replaced with fresh 93 and a bit of SeaFoam to clean out any gunk from the gallon or two of potentially bad gas that had just run through the tank.

 

[Johnfultner]

UPDATE - It's running again!

Thanks so much to you all for taking the time to write responses to this.

The bike started right up and this is what it took:

• Put in a new, freshly charged battery
• Swapped out the spark plugs (you all were correct that those "too-large" tips just come off with a set of pliers)
• Added some more gas (I find that occasionally, under half a tank, I need to give the bike a little (3 inches or so) shove forward while I'm pressing the starter to get it to go)
• Built my own understanding of the fast-idle device (the round "switch" on the left handlebar that works a bit like a choke when the engine is cold

It is the choke. The Italians always like a beautiful description. lol

 

[Monster4Lee]

Where did the last 9 days go?
It's running. Woo hoo.
Keep it so. Go ride.