Hi everyone...I just got myself a 93 sportster that was an 883 but was converted to a 1200. The previous owner also put on an S&S super E carb. It seems to miss on acceleration at about mid throttle, and surges if I keep it there. Adjusted the mixture, idle and accel. pump according to S&S instructions, seems like the lower throttle surge is all but gone, mid throttle miss still shows itself. Took off the air cleaner, seems like it improved. Tells me it might be rich. No idea what jets are in it, cuz I don't want to disable it since I just got it, and haven't ridden before this in 2 years. I'm assuming the stock jets, but won't know until I take off the bowl and check. Also, I put the baffles back in as well, but it didn't really make a difference. Anyone know if changing the jets is going to help? I'm an auto mechanic, and deal with mostly newer cars, so carbs are not exactly my specialty lol. Thanks!

 

An 883 to 1200 conversion typically calls for an increase in jet size to enrichen the fuel mix. I'd suspect the PO either didn't change the jets or installed some that are too big. Either way, you need to pull the jets and find out what is currently installed. The jet size is typically stamped on the ends of the jets. Then you can order one size bigger and one size smaller and test them

 

I only wish I knew if they put the carb on before or after thae conversion. Either way, probably used whatever the stock juets are for a super e.

 

Finally took it off and apart...found a 66 main and a 28 int. Sounds about right for the int. by the info. I've found. However, the int. jet you could BARELY see any light through. Soaked it in some top engine cleaner, then some carb cleaner, now it's clear. Just for good measure I did the same to the main, but it didn't look dirty. Letting the bowl soak overnight to get the varnish out, cleaned all the ports in the carb and blew them out. Find out how it works after I get it back on and the weather breaks.

 

OK...got it back together(kind of), and its still doing the same thing. I think i shouldnt really say its surging as much as missing. Almost like a plug wire, but at full throttle it's fine! Right now the search is on for a head breather bolt, since I decided to break mine. Cant run it and get it hot to set the carb until thats fixed. If I didn't have to support the air cleaner, life would be alot simpler.

 

The plot thickens...I replaced the intake seals, just in case. The old ones were pretty hard, not flexible. She runs better, but not like it should. Stalled once on me, and I can't seem to get the carb set properly. The jets are 66 main and 28 int., but the plugs are fouled. Had the super e set at 1-1/4 turns out, seems to be running rich, but where i have it set seems to be smoothest. It has 6r12 plugs in it, and accel wires. The one plug wire did not seem to be seated properly because the boot was too far down, but both plugs were fouled. Still coughs through the carb under medium acceleration, but that would mean its lean, and the plugs say rich. Any Ideas????

 

Bump...hoping someone sees this and can help...is it possible the PO had too small of an inter. jet and over-richened it to compensate? Maybe a lean miss causing the sputter and cough and blackening the plugs?

 

Well, got new jets...68 main, and a 265 and a 295 for the intermediate. put in the 68 and the 295, and she was running even more rich at idle, and under 3000, the surging was worse. Switched to the 265, and she runs like an entirely different bike. Plenty of power, no bogging above 3000 like the main would be too big, idles beautifully and doesn't load up and stall. Cleaned the plugs, reset the idle and idle mixture, and it's about perfect. Now, I have to wonder if she is a 1200 like the PO said, even though the vin says 883. Has a lot more power than my 83 ironhead had, but i've never ridden an evo sportster before, so i dont know if the 883 is more powerful or not. Any way at all to tell which it is? I do have to replace the rocker box gasket on the front cylinder this weekend, so if there's any way to check by doing that, I'm all ears. Thanks!

 

Depending on what year the E is, you may also have an adjustable air bleed.