Long story short ..... removed failed ignition components from my 1986 Sporty ie .Ignition Sensor , module, VOES switch and coil . Failures causing numerous problems , in particular fouled plugs . 

Have replaced with points and better ACCEL coil, ignition improved , plenty of spark and very simple .

However .... still fouling plugs and breaking down. Compression is good and still has original Butterfly carb .

Bike was absolutely screaming a month ago . Fouling is black soot .

What am I missing ??

what carb you running and did you do anything at all prior to it running like chit

One question, did you get an Accel coil matched to points ignition?

It does sound mixture related though, running too rich, but with a sudden onset. Keihin butterfly carb items to check, is the float needle seating correctly and shutting off the fuel flow? Good way to check this is by taking the float bowl base off, turning on the fuel tap and lifting the float gently to the top of its travel, see if it still drips out of the fuel inlet. Does the float have any fuel inside it?

You still running the same air cleaner and mufflers you were before? What's the oil consumption like?

My points conversion has been very successful, runs great, I grew up with points on old BSA, AJS and Norton junk so I'm not scared of them. Been running them on the Sporty since 2010.

Do you have the S&S manifold and aircleaner as well? If so, it is probably the best way to go if you and your mates are OK with its initial set up. More street cool anyway, even if it's more carb than you need on an 883. Or have you bored it to 1200?

Another cheap option is the clone Keihin 40mm CV carbs offered online. Probably made by the same mobs that make the clone S&S, but nobody is gonna care with the CV. A couple of my mates are running them, a Sporty and a 96? Indian. They both are really happy with their quality and how all the parts directly interchange with the originals. The Sporty ran great on the straight out of the box carb, although he later pried out the aluminium blanking plug so he could adjust the idle mixture screw.

The bottle cap Indian motor needed the main jet replaced with a bigger one, the slide needle lifted slightly, and the float level lifted slightly.

They bought the $150 carbs not the $50 ones but that may only have affected the retailers profit, not the quality.

But if you've got the S&S manifold and aircleaner, or can make a manifold adaptor, I reckon give the S&S a go. The CV will probably give a more flexible and reliable ride, but the S&S and points is definitely old school cool, which I'm kinda partial to.

There's a lot of stuff online about how to get a good starting point tune on a Super E. Obviously a dyno session and skilled tuner would be better, but so would be a Dyna S and fuel injection.

So let's get the sequence of events right eh?

A month ago it was running well with the 2 into 1 and the Kuryakin air cleaner.

It started fouling plugs and other problems, then you went back to basics in the ignition system and fitted points and a high resistance coil,  which is now giving a strong spark, but its still fouling plugs and running badly.

You still have the original 86, 87 butterfly carb on it, not the 88 onwards CV.

If I've got all that right, it does sound like a problem has started with the carb causing it to run too rich. So like I said first, the float actuated needle valve not seating properly and causing it to flood

Yes, you nailed it. She has 1200 kit, mild cam, 5 speed box and came with Screaming Eagle 8000rpm module. It is the original 86 Screaming Eagle butterfly Carby. To my knowledge, the tank, rear guard and midglide front end were also from birth, so someone spent way too much money in 1986 lol. Originally had factory T-Bars which I changed to Western Wide. Many people mistake her for a Dyna. I think this week we try the S & S and maybe investigate the butterfly carb. Interesting exercise installing the points, the bike seams a little angrier, until it fouls ..........   

I'd forgotten about the SE 40mm version of the stock 38mm Keihin butterfly carb that was available then, never seen one, never worked on one. I'm finding conflicting info online about whether they used standard Keihin jets or not.

Now it does sound like a rich mixture problem, and while lots of things can lead to a lean mixture, rich ones are pretty much limited to too big jets, blocked air bleeds, float level wrong, leaking float valve, very restrictive air cleaner and or exhaust.

Stock 38mm carbs for '86 had 155 fast jets and 42 slow jets, and the '87 1100 had 150 fast jets and 42 slow jets. Check the jets sizes on yours.

Another thing could be that those carbs, like S&S, are height sensitive. Setting it up at sea level then taking it up to Orange (823m?) just might be enough to make it run rich and soot the plugs.

It's probably a good idea to fit the S&S, better parts availability and more info readily available. You should be able to get it dialled in.

The "angrier" feel you mention with points ignition is probably the centrifugal advance winding more ignition advance on sooner than the VOES,  used to be several rate springs available for the advance unit, let you select the advance curve your motor likes.

And are you sure it's an '86? The 5 speed box didn't come in until 1991, and there's a shitload of difference between the 4 speed and 5 speed motors.

And one last thing, have you discovered the Sportsterpedia? Very worthwhile resource.

Yes found Sportsterpedia , a lot of great info, even  on my Carby . And yes I have also researched the 5 speed inclusion and you are right was 91 , however the bike is most definitely an 86 with matching vin and engine numbers.(checked many times lol) I have asked this question and been told the cassette was interchangeable?

You won't have to be fuckin around with points and jets if you follow this sage advice. 

As an added bonus,  your street cred should jump up a couple of notches  !

But the old shitbox needs me to look after it, no one else would bother.

An increase in street cred? By riding the same bike any dentist could buy off the shop floor? People who are into old Sporties might disagree with that, reckon it's cooler to not care. Me, I just don't give a fuck. :-)