Hey guys, I know this has been discussed to death, and I have read many of the threads on the subject, but I'm running out of possibilities:
I have a 1984 Evo FXRS converted to points (that I've set at 18 thou)
It has an S&S super E shorty with a 70 main and 29 int jet (was 28), 2into1 modified supertrapp, a push/pull throttle, a fuel filter and a pingel petcock.
I think there's a cam, and other go-fast parts in the mill, but I haven't had it open yet.

It won't idle.
It's an intermittent issue, but just when I think I've got it cured, it comes back.
(Even after several tankfuls of fuel - 91 and 94 octane)
Related issues include:
lots of popping at decceleration,
the "burp" after grabbing the throttle quickly, (which I'm sure can be attributed to the vacuum pump being incorrectly set-up because I can't get the carb set up)
and my plugs getting a bit fouled (which could be due to overuse of the enricher to get it warmed up; which I know, should be done by throttle)
Otherwise, the bike runs well.

I have tried
- tuning the carb (a few times)
- adjusting the idle speed
- cleaning the carb thoroughly (including those tiny holes in the throat)
- replacing the vacuum pump diaphragm and o-rings
(yes, I have the little blue o-ring on the "tower")
- checking, cleaning and lubing my advance weights (which show no signs of wear)
- upsizing the intermediate jet from 28 to 29
- adjusting the float
- fresh plugs (gapped to specs)
- checking (with a propane tank) for air leaks
- flipping the carb spacer over from incorrect to correct position

I'm running out of things to try.
For every one guy who says that S&S make a good carb, there's 5 more guys saying they have S&S carb issues.
I'm going to re-check/replace my points and condenser, and check the exhaust for leaks.
If that fails, I'm buying a Mikuni HSR 42.

Otherwise what's left?
Pushrods out of adjustment?
Valve issue?
Could there be something wrong with my coil? (My tach isn't working...)
Water-cooled exhaust bearing?
My carb is haunted?
Gypsy curse?
What say you?

Please and thanks in advance.

 

I had to go with a 31jet on my 85 to make it run right. try that and stay off the enricher once it starts.

 

That big huh?
I'll try it.
Thanks for the reply.

 

I like S&S stuff so much I bought one of their carbs with a 107" engine attached. I suggest you ignore the 'five more guys'! Stop asking around, except to find a local indy who actually knows how to tune an S&S. Some owners master that dark art (applies to all brands of carb!), while others, including me, simply go round in circles chasing our tail with such problems. Leave your tail alone and find an expert - you may be surprised how easy he finds it to sort it out - and the wonderful results of doing so. Simples!

 

That's solid advice. I couldn't live with myself if I didn't try on my own first though.
I'm a try that 30, 31 int jet first and then go with the pro.
Thanks.

 

Are you 110% positive that the timing is set correctly, and the ignition is in good working order?
Scott

 

Pull the advance weight spindle and make sure the hole that is drilled through the middle that the bolt passes through and connects to the cam is actually accurately drilled.

I had a engine that did the same thing and it ended up being drilled slightly offset causing the point gap to go in and out of setting.

 

I'm not positive of anything anymore.
.

 

Had to run 31/72 on a shovelhead so no 31 isn't that big. Seat the mixture screw on top gently, back it out 1 1/2 turns as your starting point. Warm the bike up now tweak the mixture in & out till it stumbles both ways and set it just a hair on fat side of the middle.

Next thing WTF is up with the propane tank ? Trying to blow a head gasket ? Ever see a dumbass set a bike on fire doing that ? I have, damn near set his garage on fire. Use carb cleaner or brake clean, something to drop the rpms not race it.

 

Pull idle mixture screw and make sure its not bent. Helped a friend who was having problems with getting his ss running right. Someone previous had run idle mixture screw into seat and bent it. Replaced, retuned carb to ss instructions, ran fine.