XL not running right 73

[Todd]

I'm working on a 1973 sportster XL can not get it runing right, it has an s&s super E shorty carb on it and is .050 over. What can I try?

[garyajaz]

whats it do/not do?

[Maddog]

hope its a late 73 at 50 over!!  like said before whats it not doing or doing?   would help to know that!!

[Todd]

It will run holding the throttle. cant get it to idle smoothly it keeps poppin through the exaust. everything is at stock settings . including points,plugs and carb. what do you suggest ??

[tomfiii]

Has anything been worked on or replaced?

[Lew]

Are the valves/pushrods adjusted to spec?

Lew

[garyajaz]

pop through exhaust.
lean.  adj slow speed and if just started with no carb work prior check for intake leaks.
also a bad exhaust gaskett may do it.  but thats just usually pop on decell.

is advance unit working?
if been sitting low speed jets first thing to clog up cause so small.

[saltcaveminer]

since the engine runs with part throttle i would start by cleaning the carb. Salty

[saltcaveminer]

check youtube videos for s&s rebuild shows you all you need to know.Salty

[Pirsch Fire Wagon]

Backfiring through exhaust is normally a lean condition caused by lean adjustment or intake leak (no matter how small - very picky carb for intake leaks). Better to run a "little" rich. The Accelerator Pump also controls some fuel at idle. So, screw it in all the way to begin with, let it get HOT and then adjust it if the S&S Instructions won't work.  Attached is the quick reference guide for tuning it.

[attachment removed after 60 days by system]

[nucklhead13]

I got that S and S Super E carb on my 1980 1000CC Ironhead. It really helped when I got a manual from S and S. It tells how to adjust the idle mixture. It also tells one should turn the accelerator pump off while doing that adjustment. It also tells how to figure out the right jets. It even tells how to test the main jet. One thing that helps is that it says the jets that work at your elevation work within 7000 feet higher or lower elevations. It tells one may have to readjust it. It also tells what exhaust pipes can do. Sine I live in a high elevation it seams to get better gas mileage with the accelerator pump left shut off. It will also tell how to adjust the float. I adjusted mine with a regular tapemeasure. One that carpenters use. The metal clip on the end of it made me adjust the float too low. At least the manual tells that can cause problems. I think the last time I looked at http://www.sscycle.com/ one could still find a manual.