I have a new S&S Super E kit inbound tomorrow. My engine is mechanically stock, 1984 Eighty inch Shovelhead.. It does have 1-3/4" drag pipes with KW Power Plus Baffles, S&S Air Cleaner, and is currently running with points. I have a stock (original to bike) Khehin carburetor. I forget the jetting. It runs and starts great but tends to get the float stuck open occassionally.

What jets should I try first? Many here say 70 Main and 295 Intermediate. S&S says 66 Main and 28 Intermediate Jets for stock 80 inchers. Thanks.

 

Float stuck open is sometimes the fuel tanks have very fine grit in them that is unseen

had you asked about that —- to confirm - when this happens riding it you shut off the fuel petcock speed up 50 MPH and when it runs out of fuel hold it wide open and turn the fuel back on - do this 2 or 3 times and it will eat anything in the bowl - it that fixes it you tanks are dirty

it could be the float spring not assembled correctly - if so it wont stop flooding after doing the above

 

It only sticks before starting after sitting a couple of weeks. After a few minutes with the petcock off, it will start and run great and then turn back on and it is fine until it decides to act up again. It is not an every sit for days affair. The engine vibration loosens it up even at idle. It did it with my old, original tanks and does it with my new to me tanks. Now I usually turn on the petcock for a second or two. Shut it off and then start it up and turn it back on.

I have the S&S inbound and am not going to sit it on a shelf and look at it. I would appreciate some Jetting info. Kheihin parts are getting scarce. I am upgrading.

 

The size of the jets are stamped on them, you can remove them from your old carb and read them. This won't be much help if your new carb is bigger, more air requires more fuel so the jets on the new would have to be bigger. I would start with what's recommened and go from there.

 

I found the 295 jet too rich for my 80" FXS with an H cam. Changed to a 28 and it runs great, although a little harder to start first thing in the morning. I think I'm running a 70 main.

 

Thanks. The 70 main sounds more like it than the 66. I will probably go with the 28 Int to start. Thanks for the input. 45,000 original miles. The only work to the engine was new gaskets years ago when I first bought it as it leaked almost everywhere as it had been sitting a long time; no leaks since! The Keihin has been rebuilt a few times plus was re-jetted by me years ago. I can't find my notes as to what jets are now in it.

If I would always remember to just open the petcock for a second or two and then shut it off until it starts it would be fine. You get complacent as it otherwise performs great and then open the the petcock after it has been sitting and reach around to find the key and then glance down and see fuel pouring onto the nose cone out of the air cleaner!

 

S&S just called and said 70 Main and 295 Intermediate as a good starting point and probably right on the money.

 

i have customers from years back that would tattoo the jet sizes on them someplace so that they did not loose then numbers

different crowd today not as much fun as back then

 

Well the S&S Super "E" is on and running strong! Very snappy throttle response! I only had to tinker with Idle screw a bit and 1/4 turn out on mixture screw. Running strong with no carb farts or decel pops. I am pretty pleased. I will do as S&S suggested and run it this way for a couple of days and then take a look at the plugs.

 

Was going to chime in, that's where I'd start with tuning, the 66 and .028 sounds like a sportster setup.

Turn the mixture screw on top in till it seats then back it out 1 and 1/2 turns, if the .0295 is right and you don't have any air leaks best idle when warm will be 1/8 turn either side of that. Shovels like that set just a hair on the fat side.