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Fouling plugs and more.

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Pnrdrmmr

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I have a 1993 1200 sporty, i bought it a few months ago as a small fixer-uper. we got it running, and it ran pretty strong other than some lurching in the higher rpms. while i was tweeking it it just died on me. so we tested all the ignition wires, plug cables etc, everything was fine. we hooked it up to my car with the dead battery off and it fired up after a few tries. so i charged the battery and it ran next to perfect for a few days. took it to school on the freeway, went smooth and comfortable at 60-65 no prob. but the next day when i went to go to school, the battery was dead. so whatever, i went to school and during my break i come home and hook it back up to my car to see what the deal was. needless to say, it started right up. but now it backfires like crazy and runs like (EDIT). i checked the plugs, and they had massive amounts of carbon buildup on them, they only have 50 or so miles on them. i cleaned them off and it started up and ran fine for a few seconds then started backfiring again.

I have been told foul plugs will make it backfire, and that the jets i have a to big for where i live, the main is 170 and pilot is 45.

any type of help would be appreciated. this is my 2nd bike, but the first one i have had major problems with. i don't have the money to take it to a shop and have the fix it. i'd rather do it myself and learn.

Please read and understand the info in this link...

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Welcome Pnrdmmr, to the HDTimeline forum...where there are plenty Self Help Tips and threads to help you troubleshoot your ride and make HD ownership more enjoyable.

That said, it sounds like you may have several problems, but you will need a few things. Do you have a simple digital multi meter (DMM) or charging system tester? Either one can be picked up at Harbor Freight for $8 or so. Do you have a service manual or at least the owners manual? If not the local library is free...though you will want to spring for the HD Service Manual ($60 or so well spent the first time you use it for service).

1st problem sounds like the battery may be old and have a bad cell (they can actually self discharge themselves if there are some deposit salts internally shorting the cells out. Fully charge the battery and take it to Autozone or O'Riellys/Kragen and have them LOAD test it. Fully charged the battery should be 12.6-13V and when put underload should not drop below 10V. Pick up small tube of dielectric grease ($6) While the battery is out, clean all the high current black and red cables (both battery cables and the starter cable, scraping them til shiny with pocket knife and coating them with that dielectric grease to prevent water/corrosion intrusion from degrading the contacts again. Also roll back the insulation and see if the wires are green or corroded (you may have to replace them).

2nd problem is fueling, you may have bad gas or debris clogging the works. The carburetor bowl has a drain screw, use a dixie cup to catch the drainings, when you open the screw and inspect what comes out. If lots of rust/dirt or it smells like old varnish, you are probably looking at cleaning out the works. So be prepared for a weekend of cleaning things, draining the tank and inspecting fuel tank screen, tank (drain old gas and swish around w/ alcohol, SeaFoam or Chemtool), flush fuel lines and retry. The last resort will be to perhaps pull the carb and possibly rebuild it (kit is about $50). You can break down the above in stages, put everything back together and try, but usually at some point you are going to do this anyway. I cannot stress the importance of having a manual...even a Clymer one at $40 is better than nothing.

http://www.hdtimeline.com/fuel_and_carb_related_issues/11050-understanding_cv_carbs.html

Take plenty of digital pictures as you take things apart and lay them out like the exploded diagrams and use masking tape to label everything. The carb has lots of small parts easily lost, so that part is the final thing to troubleshoot.
 
NEWHD74FAN has given you so great advise.......LETT US KNOW how it all works out!we live for stuff like this lol
 
Alright, so I checked the gas, all fine, but I cleaned the carb anyway just to be safe. I took the battery completely off, and hooked it up to my car. Still backfires. It makes it impossible to ride like that, its so lurchy.

When I hooked it up to my car, it ran pretty good for a minute or two, with minimal backfiring. Only a few small ones and not often. but when I'd open it up, it would bog down and almost die, before catching up. Almost like its flooding. I've tried adjusting the mixture screw and it feels the same at whatever position I have it. I am thinking the jet is to big still.

I think the timing may be off, but I don't have a timing light to check. I have an old 63 bug that did this same thing almost and when we set the timing it ran a lot smoother. Does that sound like it could be the case with this? or am I just over analyzing?
 
Are you smelling raw fuel coming out of the pipes when it is idling?.
The pipes Black & sooty ?
 
Did you check the enrichener cable?? Take it out and see if the starter valve(27583-88) is black, also check to see if the little black ring is dished, if it is that could cause it not to seal and leak giving your overly rich conditionand can foul a plug.
 
i checked the enrichener, all's fine there. What has me worried most is the backfiring, makes it nigh impossible to ride. I think the timing may be off, and have been told it may be.
 
Here's a problem a bud had with an '84 FLH, doesn't cost anything so worth a check. He had intake leaks and the VOES had a broken wire, spray some wd40 with the bike running around the intake manifold around the head flanges and at the carb mount seal to check for leaks if the idle changes you have a leak....then take a pair of long nose pliers and squeeze off the VOES vacuum line...the idle should change if it doesn't it's not working.
A Factory service manual is a pretty good investment too,they'll save you a bunch of bucks in the long run
 
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Also check ignition is it stock any recent changes good luck
 
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