At a loss... Here's the situation.

Bike was running fine, but took a little bit of time (30 seconds to a minute) to come back down on idle, little chug at beginning of throttle, and occasional small coughs from air box and exhaust.

Decided to buy new factory pro needle jets. Went in real tight.
Raised float at same time. Reassembled bike. Wouldn't start. Too much float.
Lowered float. Bike doesn't start. Pull the throttle while starting, bike fires right up, but idles too high. Lower idle, play with mixture screws for about 2 hours, can never get it to the right spot:

-Won't start without throttle (even warm), starts with throttle everytime.
-Idle won't stay steady. If its at ~1.2k, it'll drop and die. If higher it'll stay there and not drop, but that's too high.

So frustrated... Putting in a new needle jet shouldn't make it worse ><

Sounds exactly the same as my M600 I have just bought!

Have you tried syncing your carbs?

What level are the floats set at now?
Idle mixture screw setting?
Check for inlet manifold air leaks.
Carbs should be synchronized as suggested.
Little o rings under carb caps didnt fall out or get pinched?

Quote from: koko64 on May 10, 2012, 12:51:02 PM
What level are the floats set at now?
Idle mixture screw setting?
Check for inlet manifold air leaks.
Carbs should be synchronized as suggested.
Little o rings under carb caps didnt fall out or get pinched?

How about the o-rings on the main jets?

Good condition?

+1 on carb syncing.  That can be the difference between a bike that barely runs and one that runs great.  That could explain why it starts with throttle and not without as well.  The position of one throttle plate relative to the other changes between when the throttle is pulling it off the stop and when it is resting on the stop.  So it could be that the carbs are too far out of sync when resting on the stop, but when pulled by the throttle, they're close enough.

Another idea in addition to those that others have given: check your vacuum diaphragms at the top of each carb for leaks (hold them up to a light and see if you can see any light coming through).

Good luck!

If it is not popping and backfiring when the revaluation are up, then it sounds like a problem with your pilot circuit, of either, too rich at lower rpm and adding enough throttle brings in enough air to compensate or too little and bringing in enough air is moving the slides enough to get into your needle circuit.

What size pilot jet did you use from the kit?
Also, I have been working with factory pro trying to figure out a carb problem with my bike. They were extremely helpful and responsive through email.

Update. Running now, but not perfect.

Floats were still not right, apparently at idle this is very important. I called the friendly gents at factory pro and got some insight on how to correctly measure the float and set it to 14mm.

Didn't replace anything except for the needle jet and played with the floats.

Haven't tried syncing carbs, decided that I'm going to wait until I get a jet kit and replace everything, then sync the carbs.

Idle mixture screw is at 3.5 turns out right now. Still playing with this. Little o-rings under caps are still there.

Have not checked the o-rings on the main jets, if I need to replace them, can I just pick them up at a ducati dealer?

The dealer should be able to get the main jet o-rings.

My dyno-jet kit came with new o-rings.

Quote from: makowb on May 11, 2012, 04:55:38 PM
Have not checked the o-rings on the main jets, if I need to replace them, can I just pick them up at a ducati dealer?

IMHO it's good practice to use new o-rings on the main jets every time you change them...

I still always get the best results setting the floats with clear tubing. hook it up to the nipple at the bottom of the bowl and open the screw. I use a long line and make sure the other end is thrown over the handlebars or something. Just something to make sure the line goes up. then when you open the screw, the fuel level will go up to the fuel level

What is the state of your carburetor vent lines?  After I closed the holes on mine my idling (after rebuild) problems disappeared.  Cold weather starting also improved greatly.

Huh, missed that it is old thread.