Request for assistance - Dellorto 40mm on Ducati 900 Replica

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Craig in France
Paso 906
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Re: Request for assistance - Dellorto 40mm on Ducati 900 Rep

Post by Craig in France »

tricatcent wrote: My needles only have three grooves. Is that correct?
Yes.
tricatcent wrote: I lowered the needles a notch. That has helped a lot with the rich running.
Ok, but be aware that you may be/probably are masking the real cause. You might like to think about changing the idle jets, if the rich running ocurs below half throttle. And/or the main jets and the needles, if it occurs above half throttle.

And before all: check your float heights.

HTH

Craig
tricatcent
Cucciolo - the Lil Pup
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Re: Request for assistance - Dellorto 40mm on Ducati 900 Rep

Post by tricatcent »

I have checked the float levels. I think there may be a problem with something blocked in the rear carburettor to do with the idle circuit. One thing I have noticed that may be non standard is the extension on the manifold where it goes into the urethane insulator has been filed to a point. I don't think it would have been this way when it was new. It seems to me the reason why someone would have done this would be so that an O ring could be placed in the triangular pocket. With an o ring there there would be no leak even if the insulator was cracked. I am going to try an O ring in there.

There are a lot of small things that have been altered on my bike because it was a race machine for many years and with the frequent tear downs little things like this were done each time.
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