DELLORTO PHF 32A (D) CARB SETTINGS FOR 1974 250 DESMO

desmo_duke1 · Post by **desmo_duke1** » Tue May 18, 2004 2:49 pm

Hi
Having problems tuning this carb.Anyone know what jet sizes I should be
using.? Have the following jets fitted.

125 main
65 idle
50/3 slide
33 pump
AB265 atomiser
K3 needle
75 choke
What is the idle RPM supposed to be.?
What is the basic setting for mixture screw(turns out).?

Thanks
Alan

Eldert · Post by **Eldert** » Wed May 19, 2004 7:38 am

Hi Alan
I would try a K1 or K6 needle . they are 2.45 mm diam
the K3 is 2.5 mm
you can find a needle chart at the Ducatimeccanica site

Eldert

desmo_duke1 · Post by **desmo_duke1** » Thu May 20, 2004 11:55 pm

Hi Eldert

OK....Thanks.!!

Alan :D

Vulpine2 · Post by **Vulpine2** » Tue May 25, 2004 3:36 am

I have the same bike. Standard fit was a square bodied Dellorto 29VHBmm carb, which was also fitted to the 350 and 450.
I don't have any info about the 32mm, which presumably came off a Darmah or similar? Haynes states a 125/122 main jet for the Darmah, so in comparison a 125 for a 250 would seem a liitle OTT
When my bike's (eventually...) back on the road I intend to fit a less restrictive silencer and replace the worn original with a new 30mm Dellorto plus K&N.
On enquiring with those that know about these things I was advised that anything above 30mm would be overkill unless the engine was heavily breathed on.
Be interested to know how you get on!
Cheers

droydx · Post by **droydx** » Wed Oct 27, 2004 8:36 pm

I'm running a 32 PHF on my 250 widecase.....it did take some finicking around to get it pulling smoothly through the RPM range. I have a green white cam, stock compression, ignition and it runs strong. Syd Tunstall smoothed the ports and I have one of his low megaphone pipes with an insert. It is easily streetable, but way loud!.
I'll have to pull the carb to check it and see what I have in there...didn't take any notes and I've had the bike for a loooong time. I'll check back tomorrow with what I find.

Ciao