Standard carb settings for 750 Sport

andygbsmith · Post by **andygbsmith** » Sat Aug 01, 2009 5:45 am

My sport has developed a flat spot just as you open the throttle, I have just fitted K&Ns
I know it's running rich so before I get to involved with pilot jets, pumps, etc I wanted to check the carbs are set standard and not played with.
I can't find the info so can someone point me in the right direction.
Andy

abmartin · Post by **abmartin** » Sat Aug 01, 2009 7:23 am

Hi Andy,

According to my information with your bike's 32 mm carbs you shoud have an SK17 needle in the second position, a 125 main, a 65 pilot, a 60/1 slide and a 265AB needle jet.

I have never found K&N filters to have much effect on any of my Ducati's operation but you should make sure the carbs are properly balanced and adjusted.

Bruce

andygbsmith · Post by **andygbsmith** » Sat Aug 01, 2009 1:08 pm

Thanks for the info, I agree I have never found much of a change when fitting K&Ns before so there is probably something else going on, so while I'm pulling the carbs apart I thought I would check everything.
Andy

Den · Post by **Den** » Mon Aug 03, 2009 5:42 pm

According to my information with your bike's 32 mm carbs you should have an SK17 needle in the second position, a 125 main, a 65 pilot, a 60/1 slide and a 265AB needle jet.

I have never found K&N filters to have much effect on any of my Ducati's operation but you should make sure the carbs are properly balanced and adjusted.

It is my understanding that the specification of SK17 for the needle was a misprint in the original parts manual and carried over to many other Ducati reference books. I believe that a K5 is the correct needle.

In my experience a hesitation, and/or spitting back as you crack the throttle, is a sign of a weak mixture. If after synchronizing the carbs and setting your idle speed you still have the hesitation try backing out the mixture screws 1/8 turn or less.
.

wdietz186 · Post by **wdietz186** » Tue Aug 04, 2009 6:40 pm

I agree with Den,It sounds like you are too lean and the mixture screws will likely cure your problems.The taper on the screw is short and very sensitive to even the tiniest adjustment.But make sure the pilot jets and idle circuit passages are clear before you spend too much time adjusting things.All the bevels like to be on the fat side in the initial throttle opening.As for the needles they don't really have much effect until the throttle is open over about 3/8 of the way and that is more a midrange issue.

andygbsmith · Post by **andygbsmith** » Wed Aug 12, 2009 11:51 am

Well as I thought it was to rich I wondered about the chokes and ended up changing the choke pistons for new ones.
This has sorted 95% of the issue and before I go any further I am going to re-balance the carbs and see if that cures the slight hesitation I still have.
I will keep you posted.
Andy