1st Stage Jetting complete on the 906

[higgy]

current jetting
idle 65
ET f27
main 190
very close runs well to 90 mph
just a little tweaking on the AC jets and I think I am there.
Got a long ride to Pocono today to check out the settings.
AFR fairly stable between 12 and 13.5 till WOT anyway

[micklm]

Higgy,

Thanks for the ongoing updates - it's great to see development work like this documented so well!

On the other hand you are making my life hard! You see I have a set of mikuni carbs borrowed from my supersport rebuild that I was going to put on the old 906. The thing is though, my Weber is performing really well. I'm getting around 18.7km to the litre (pretty close to the 5L/100km quoted above in this thread or 44mpg in US gallons, 52.8mpg in UK gallons if I have got it right). Now you seem to have shown the way forward to sorting out some of the annoying character traits of the weber.....I'm running out of excuses to ditch the weber!

One thing remains in my mind as a problem - maybe you have a solution already? Carb icing. I know Ducati made a factory kit to get warm air off the horizontal head to flow over the weber and it's intake manifolds and the later mikuni carbs had either oil or electric heating options for the bowls. The thing is I have the kit for both Mikuni options but no idea if this is needed for the Weber or if there is an easy know fix? I guy I knew in NZ wrapped the intake manifolds on his Paso with insulating tape as it was running so badly in cold weather.....

Any thoughts?

cheer mate,

Mick

[higgy]

One thing remains in my mind as a problem - maybe you have a solution already? Carb icing. I know Ducati made a factory kit to get warm air off the horizontal head to flow over the weber and it's intake manifolds and the later mikuni carbs had either oil or electric heating options for the bowls. The thing is I have the kit for both Mikuni options but no idea if this is needed for the Weber or if there is an easy know fix? I guy I knew in NZ wrapped the intake manifolds on his Paso with insulating tape as it was running so badly in cold weather.....

Actually I do have some thoughts on carb icing. I am thinking that there is an old Honda phenolic block around that would take the place of the current spacer block. Honda blocks came with tubes for coolant passage as well as some old fiat spacer blocks. Both are about the size of the Ducatl spacer block for the weber. so I am thinking the only issue will be tapping the coolant lines. Radiant heat from these kind of blocks works much better than warming the air to prevent icing. I am also thinking it will help the weber deal with baromatric changes as both of these companies made the edition for fuel economy . So once I have the weber jetting complete I plan to look into this sort of phenolic block for my 906. I will keep everyone posted as to how I sort it out in the end
BTW,The ride I took over the weekend included 240+ bikes mostly Harleys Everyone loved the sound they heard from behind the PASO. The combination of Weber and Rennsport is really unique!! The closer I get the jetting the sweeter the sound gets...............

P.S. I have a complete setup of Mikuni as well,thinking I will sell them or trade them for a spare weber and airbox, The more I work on the weber the more I feel it only adds to the soul of the Paso and to me that is what having a PASO or any old Ducati is all about

[higgy]

So far here is where I am with the weber
4.5 auxiliary venturi's
65 idle jets,adjusted up slightly rich on the air screws 11 AFR, very good off idle performance at this setting
175 AC planning to go down on these,still lean on the main at WOT,perfect mid range,really runs well no flat spots at all,very progressive and reponsive till I hit the flat spot at 90,If I close the throttle I can modulate through to get about 110mph which would indicate to me an airflow issue, but we shall see.
195 main jet
the rest is still stock,at least the WEBER,wide open airbox with K&N filter,dyna coils(3ohm)
Rennsport exhaust with the packing long gone
AFR is ranging 12 to 13.2 except WOT which sitll goes lean to 16 on the AFR
I am thinking I will go down on the AC jets and only go up on the main when the midrange starts to lean out, may not have to change the ET's at all if the combo of main and AC can fix the WOT leaning
Not seeing any reason to go up on the pump jets so far.

[higgy]

Our Weberology Document is here for downloading your own copy
http://mysite.verizon.net/vze2hw9t/index.html

It has also been made available here in the document section thanks to G.
Thank you G.
FYI
It will be updated regularly as we discover new things and make improvements aka 750 adaptions