fouling one plug only

[stef]

The vertical cylinder plug is fouling pretty bad. Black deposit all over.
the horizontal one is fine, nice tan colour.
To try and fix it, i have :
-reset the idle mixture screws on both carbs, to 3 turns from fully in.
-Synchronised the carbs.
-checked the air ducts.
-injected carb cleaner in the carbs..
any idea anyone ?

[Rockhopper]

Is it black and shiny or black and sooty?

[stef]

black and sooty mainly..

[Rockhopper]

So its running rich then. The V twins always run differently on each pot, the rear one tends to run hotter than the front becasue its airflow is not so good.
It needs setting up with a CO meter into the exhaust pipes.

[stef]

thanks, but what is it that needs adjusting ? i can get one of those coloured sparkplugs wich will tell me when the mixture is right, but i have no idea of what adjustement i can do. the only screws i can play with are:
-idle speed
-idle mixture
-carb balancing.
I have set all those.. what else is there ?
is there something in the carb itself i have to tinker with to adjust the mixture in the vertical carb?
cheers.

[Rockhopper]

Can't help you with that one! I've always prefered to get my bikes set up on a CO meter (by Nelly at Cornerspeed) after struggling with one of those clear plug things on the car.
On the FI bikes the idle mixture sets the mixture right though the rev range. Three turns out is not good enough, you need to set it to give the right CO reading. And like i said, the rear pot will be different to the front one.
Unless there is a fault on one of the carbs.

[stef]

ok, i might still buy one of these plugs, and tune the mixture screw..as you said, i hope there isnt a fault on one of the carbs though..

[stef]

Actually, does anybody know which way round to turn the screw on the carb to make the mixture leaner/richer? i might just have a go at that...

[bod]

Don't quote me on this but turning it outwards would increase fuel flow,so making mixture richer.

[eonan]

Here you go Stef...from Lance Busch [Ducati Suite]

http://www.buschandbusch.com/ducatisuite/carbadjust2.jpg

[Zimbo]

I wouldn't bother with the colourtune thingy myself, never found them much use apart from setting the idle mixture. A CO2 meter in the exhuast is more accurate and easier, probably cheaper too as a one off to have it done properly rather than buying the colourtune kit.
You may well find it's down to a worn needle / jet or emulsion tube, the needle heights are adjustable so you may be able to sort it out on that, but without a proper reading of mixture you're working completely blind.

[stef]

cheers.
in the light of this, i might just get a stage 2 dynojet kit and replace all the needles.

[Rockhopper]

Its CO you measure, not CO2!

Also you can't just stick the probe down the exhaust pipe, you need to connect it to the tap off point in each exhaust header (becasue the two pipes are connected under the engine so you can't read each cylinders correct CO from the tail pipe).

[stef]

i had a quick go at closing the idle mixture screw two turns (just on that cylinder), leaving it open only 1 turn. Then went for a 20 miles blast.
i stopped quickly, and checked the vertical plug.. still fouling. so i suppose it isnt a question of finding the right setting on the screw, since whatever position it is in, it is too rich.
So it is probably something not quite right within the carb... i'll start stripping tomorow.

[richard horton]

try checking the float height - 14mm - carb inverted - from the float bowl gasket face to the highest point of the float - adjust by bending the thin steel contact face for the needle valve :look:

[stef]

i could do that pretty quickly, since i took the carbs apart last night.
the "faulty" carb is spotless. i was expecting loads of gunk, but it's shiny.
the main needle has lost it's shine though, and looks a little dull. this could be a sign of wear ?
so i'll check the floats anyway.

[Kato]

Stef...Did you ever get this sorted, would love to know what you did my bike has the same problem...

[Sparky]

If you look at his reply to thread below he explains all.

http://www.ukmonster.co.uk/monster/showthread.php?t=18186

Chris

[stef]

yes, the Oring around the main jet was gone. completely dried out. the main jet was not a tight fit in the cavity anymore, it was just wobbling all over.
cost me a fortune. around £0.50.
bike is now running fine, although maybe a tiny bitrich, but that's because i havent adjusted the mixtures screws. i'll have to find someone with a CO2 analyser to do that.

[Lowsider]

Either buy your own........

Ebay (http://cgi.ebay.co.uk/CO-2-Gas-Analyser-exhaust-gas-tester-co2-tester_W0QQitemZ8072064639QQcategoryZ30921QQrdZ1QQ cmdZViewItem)

Or as you are in leeds My mate runs Motostrada he set up mine and is very good and very good value... Link Below

[stef]

the ebay one looks tempting, but i cant be bothered collecting in hants..
moto strada, is that in shipley ?
if so, i ride/drive past it every day.

[stef]

i just follwed your link, and it is where i thought it was.. nice one, less than a mile from my work place (saltaire).
i might pop in there tonight for a quote.

[Lowsider]

Jason Sutcliffe is the guy you want to see. He's spot on used to work for Ducati Leeds then set up on his own. He is a main dealer for Moto Guzzi and handles anything italian especially women...

But be carefull he has an S4R in stock that looks the mutts as well as a matching pair of 04 R's ie 749R and 999R.... God I could spend some money in there.....

He did my Dynojet, Termi's Service and various other jobs for me.