94 FE350 - Dellorto VHSB 38 missing the idle emulsion jet?

I am having trouble getting the bike to start without choke and idle. It needs choke even when hot, starts and goes up to an enormous amount of revs. Turn off the choke and it will die. If I am quick on the throttle after closing the choke, I can run it with the throttle, but I have no idling at all. Then, it won't start unless I operate the choke again. Carb has been cleaned several times with compressed air, cleaning needles and even ultrasound bath. No difference. I do appreciate that the culprit in this case is the idle circuit of the carb (idle jet, air screw, idle adjustment screw), but I have found something intriguing.

Now, in some of the Dellorto part catalogues (and manuals) there is an "idle emulsion jet" also called "inner idle jet" which sits under the idle jet itself. When I took the car apart this morning and removed the idle jet, there is no such jet/emulsion tube at all! What gives? In the Husaberg parts manual for the year, there is no such part either.

So: should there be an "inner idle jet" or not? Certainly looks like it would fit since the placement is threaded all the way down. I am talking about jet no 4 in the picture attached

Taffy said:

As Eric says.

The CD1 (CD one) jet is helpful for electric start. it has nothing to do with your problem though.

I sell atomisers and needles, pilot jets. etc.

I do a kit called 'easy start' and the dea is that it repalces all the worn out parts. It consists of;

Needle
Atomiser
fuel valve
2 O rings
fibre washer
the correct PJ I think you'll need.

cheers

Taffy

Click to expand...

Alright. But I can't see your kit for VHSB flatslide carbs, only PHM or other roundslides. Link to VHSB kit please.

No matter. I fixed the problem and the bike runs ever so sweet. Starts on the button, idles and revs like it should, unsurprising with the rebuilt engine with 0 hours by Thomas of Enginehardware in Sweden.

For the benefit of other people here, this was the problem: In another thread I posted some time ago where I needed a new intake rubber (unavailable) and bought an adapter consisting of a (beautifully machined) aluminium flange and intake complete with a modern style rubber muff to fit Dellorto 38 from Portugal. This is a part for classic Husqvarna bikes but fits with some slight mods. The first thing was to file away some material on the top of the flange. Otherwise it would foul what seems to be just an empty lug in the Husa cylinder head. Well, I didn't notice that there's another lug below the intake which needs to be filed down to clear the bottom of the flange. This time I opted to file away just a little material from the head itself, under the intake. Fitted all back and problem solved.

So, in essence, the problem was due to the engine sucking air after the carb. I'm well chuffed and to celebrate this occasion, I attach a picture of my 1 year old Karelian bear dog-Laika-Border collie mix called Taffy in his happy space. Why is he called that? Well, his best mate is a pure Border collie called Scott, so I reckoned that I should honour Wales as well as the Scottish borders. But to be honest, he's named after a very good army mate, William Rhys-Davies, former SAS sniper and Guinness book of records holder.

Also, this manual had the designations for the standard jets of both the roundslide and VHSB carbs. As well as everything else for the 350-400-501 of the 1990'ies.