air bleed screw settings - Ducati.ms

SP544 · Jun 28th, 2010, 6:04 pm

I have an 08 standard Hyper with stock ECU, LV cat eliminator and muffs. I installed a Fatduc and set it to approx 1 o'clock. It has helped a bunch with the idle characteristics and running. I started to adjust the air bleeds and noticed the vertical cylinder air bleed screw does not do much. I can fully close it without dramatically affecting how the bike runs. The horizontal cylinder air bleed screw is so much more sensitive. If I turn it all the way in the bike will die and turning it out the rpm's come up. Is this normal? I have been running them both set at 1 1/4 turn out, but the idle just doesn't feel right.

SP544 · Jul 2nd, 2010, 12:28 pm

Anyone have any ideas? Should one be more sensitive to adjustment than the other? Also, does turning them out make it allow more air in to mix with the fuel and make it leaner?

**CDONA** · Jul 2nd, 2010, 1:05 pm

My only guess, some kind of air leak on the rear cyl. front cyl. results fine. Charcoal canister hose/nipple? Lightly spritz water around gaskets, joints, hoses while idling, a change in idle will occur if there is a leak. Look for the sync and slack between injectors controlled by the throttle cable. Mine is stock with fatduc, both 1 1/4 turns out.

HYPERR · Jul 2nd, 2010, 8:45 pm

Quote:

Originally Posted by SP544

I have an 08 standard Hyper with stock ECU, LV cat eliminator and muffs.

SP, when you say muffs, are you saying the stock mufflers or the LV slip ons? The reason I'm asking you is because I also have the LV cat eliminator and was thinking of getting a sil moto italia slip on and was wondering if I can get away with the stock ECU/fat duc combo.

SP544 · Jul 15th, 2010, 8:21 am

SP, when you say muffs, are you saying the stock mufflers or the LV slip ons? The reason I'm asking you is because I also have the LV cat eliminator and was thinking of getting a sil moto italia slip on and was wondering if I can get away with the stock ECU/fat duc combo.
Jul 2nd, 2010 6:05 pm

Hyperr, I have the LV cat eliminator and slip ons. It has been OK, but sounds like I have an air leak to track down. You can get away with the fatduc and stock ECU. I have read on hear several have done it.

CDONA, thanks for the reply!

dhc8guru · Jul 15th, 2010, 3:30 pm

You need a throttle body balancer or mercury balancer, carb balancer..whatever you want to call it. Adjusting the bleed screws really doesn't change the idle that much like maybe a few hundred RPM through out the complete. If your only adjusting one, you really would probably see almost no difference. If you are using a balancer, you would see the mercury rise or fall quite a bit depending on how much the adjustment. Anyways you adjust the bleed screws to get the throttles balanced and also fine tune the idle to specs.
You may need to reset the idle stops on the throttle butterflys. The vertical cylinder maybe carrying the a majority of the idle condition.