[470four]

Hiya

Just rebuilt my carbs with new gaskets & emulsion tubes, in doing so one of the needle assemblys slid out with all the washers falling off... the circlip & washer on the needle is good, stayed in place - wishing to know the order of the two washers under this - I have a stage one dynojet fitted by the prevoius owner which & have no instructions for

There is a normal size wide washer (wide width, not depth), and a smaller one - I take it the wider one goes on the needle first?

Any help or instruction scans much appreciated!

 

[Rock Store]

The smaller diameter washer slides on first,seating against the nylon washer,followed by the larger washer .I generally just use the larger washer.The euro Mikunis were diferent then the US models,needles,jets etc,perhaps thats why the smaller washer is their....Either way larger washer last!

 

[buffalo]

Full instructions for any of their jet kits can be found on dynojet.com Just find your jet kit and click on the little PDF symbol.

 

[470four]

Thanks Guys! :think:

 

[470four]

Dammit....

Bike is back together with new carb gaskets (top small o-ring, jet holder & float bowl), emulsion tubes & mixture adjustment screws (checked & double-checked at first 2 1/2 turns out, then just now at 2 turns out as per Dynojet instructions)

Bike will fire & run fine - until it gets hot, then under 3-4k it will stumble, run on one, stall on tickover & generally Not Run Well...

Both plugs are sooty black, indicating its far too rich? I have disconnected the choke & made sure the shuttle was pushed right back thinking the choke may have been stuck on but no luck.

I have not messed around with: Needle positions, float heights or jet sizes as the bike ran fine before, if a little snatchy at low revs due to the worn emulsion tubes?

Any ideas please??


** Just doublechecked & yes - they have supplied the right emulsion tubes.

 

[470four]

Quick question - mixture screw is in(clockwise) for weaker, anticlockwise for richer, correct?

 

[Serious Black]

Quick question - mixture screw is in(clockwise) for weaker, anticlockwise for richer, correct?

Correct.

Check that the choke is seating all the way before you start farting about with the mixture.

 

[MitchB]

Went through this recently myself.

This post should help:

http://www.ducati.ms/forums/57-supersport/137473-jetting-advice.html

Reading this, and the DynoJet / Factory Jet Kit literature should provide a lot of help. Sorting these carbs is not quick, as the jets and needles are not easy to access - but use patience and lots of testing, and you'll find that the Mikunis can be made to run quite well.

 

[470four]

Took the carbs off again today (getting good at it now ), doublechecked the new mixture screws & emulsions were EXACTLY the same as the old ones - all good!


Choke mech was working well & free to move - decided to check the float heights - a little research showed the float height to be 14mm?

Mine were 10mm and 11mm... This would explain the rich running, but confusing - as it ran fine before? Set both to 14mm.

Further searching tonight shows Ducati tended to set them on the rich side, & not always the same heights? May be worth checking! The bike is back together again & ready to start tomorrow.

 

[AbqDave]

If you hold the needle upright (pointy end down) the thick nylon washer goes under the circlip, and the thin metal washer goes under the nylon washer if you want. If you omit the metal washer you will run a half-notch leaner.

So working from the cap down to the hole in the slide:

Cap
Spring
There's a nylon fitting on end of spring that fits into top of needle
Circlip
Thick nylon shim
Thin metal shim
Slide

That's the stock setup, which also works for Factory Pro, if have any parts left over yeah you have to go to the manufacturer's website

Two thoughts --

1. Worn emulsion tube will make it run like absolute crap, super rich in that 3-4K range
2. Check the o-ring on your main jet, if that's old it can run rich.


The latter hint courtesy of the head tech at PJ's in Albuquerque, who I think is awesome, even though he looks at my SS much the same way a haughty maitre-d might look if I tried to bring a one-eyed mangy pit bull with me into a fancy french restaurant.... but it's all good. Least it didn't blow up on his dyno.

 

[470four]

SORTED! Correct float levels seemed to have done the job, plugs are now a perfect biscuit colour...

Set float height 14mm from the base of the carbs - float to be resting on - but not compressing - the spring pin on the float pin.

My slide needle arrangement - as per dynojet instructions:

The small washer is a pain to keep in place refitting the needle into the slide... nip the needle with longnose pliers just behind the washer & lower it down into the slide.

 

[tedjeparre]

I was reading this old topic, and had a question: how do you adjust the float heights?
And if you want to put other jets in the carburetor, can the carburetor stay mounted on the bike or better to take it off the bike?

 

[ducvet]

to change float height you gently bed the tab the needle touches.

You will want to at least remove the airbox and if you have not done this before I suggest you remove the carbs to better see / understand what you are doing.

 

[tedjeparre]

Thanks ducvet, i'm going remove the carbs. Then i can also check some other things