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My '01 750 went into the shop today. About 2 weeks ago, it started flooding starting cold (even if no choke on) requiring spark plug removal and a cylinder blowout. I just bought the bike about 2 mos. ago, used w/ 2500 miles. I know the Mikuni carbs were rejetted when the previous owner put the Termis on it and I suspect sticky floats. I didn't find much related to this in a search of the board. Does it sound common?
 
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I've also got an 01 M750. Mine has Staintune cans (with the street baffles in) with the stock carbs and the stock jetting (and more miles than yours)...and it runs great.
 

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My '01 750 went into the shop today. About 2 weeks ago, it started flooding starting cold (even if no choke on) requiring spark plug removal and a cylinder blowout. I just bought the bike about 2 mos. ago, used w/ 2500 miles. I know the Mikuni carbs were rejetted when the previous owner put the Termis on it and I suspect sticky floats. I didn't find much related to this in a search of the board. Does it sound common?
It could also be a lousy re-jetting job... I rejetted my '99 M750 at about 60,000km with a FactoryPro jetkit. With Staintune slipons (without baffles) and an opened airbox, even the middle of the 3 supplied jets was _way_ too rich. The kit comes with a 137.5, and 140, and a 142.5 as well as a new needle with a noticably different taper to the stock one. I read the instructions that came with the kit and decided to run the middle (140) main and the needle in the middle position. Ran it up on the dyno and it was _ludicrously_ rich. I've ended up with the needle clip in the top groove (using the FactoryPro needle) and the stock (132.5) main jet, and the air/fuel ratio (at WOT on the dyno) now as close to spot on as I can be bothered getting it... If I'd left it at FactoryPro's recommendations and not checked it on a dyno, it'd be running way too rich, and I suspect fouling plugs regularly...

big
 
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It could also be a lousy re-jetting job ... If I'd left it at FactoryPro's recommendations and not checked it on a dyno, it'd be running way too rich, and I suspect fouling plugs regularly...

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It ran fine for the month prior to this so I don't think it is a botched re-jet. Are there any diaphragms or accelerator pumps in the Mikunis which could possibly cause a leakdown from the bowls while the bike is sitting?
 
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I don't think there is anything in those (idiot) Mikunis that causes fuel to flow when the bike's sitting. Except for a stuck float. But I think if you're float is stuck, wouldn't fuel just drain out the drain tubes? There wouldn't be much due to the vaccuum-operated nature of our fuel pumps. In any case time to take the float bowls off and see what's what. Get the schematic off the Ducati website, if you don't already have it.

PS mine has always run great, except for the occasional drip due to the crappy float bowl seal (on my list of things to fix).
 

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The carbureted Monsters have both a vacuum operated petc0ck, which prevents fuel from flowing when the engine is not running, and a vacuum operated fuel pump, which pumps fuel under light pressure, much less than an electric fuel pump. When the bike is sitting, very little additional fuel could flow into the float bowls.

If it is a sticking float, whacking the carburetors with something hard, like a screwdriver handle can often free it up. You might try pounding on the bottom of the carburetors to see if the problem goes away for a while.
 

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The carbureted Monsters have both a vacuum operated petcock, which prevents fuel from flowing when the engine is not running, and a vacuum operated fuel pump, which pumps fuel under light pressure, much less than an electric fuel pump.
 
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Discussion Starter #8
It lives ;D

Somehow, the idle mixture screws were about 6 and 6.5 turns out :eek:

Next time, I'll look at it more closely.
 
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