HELP!! 04 1100 custom not firing on rear cylinder...
Guys I need help racking my brain here...I bought an 04 1100 Custom back in October that had been sitting for almost a year but had been started here and there. Bike rode great and all things considered ran pretty good, but had a little bit of a pop/back fire to it here and there. Rode it for several weeks trying SeaFoam and a couple other fuel system cleaners but nothing worked to get rid of it. Finally tore the carbs apart and cleaned them and found a good bit of gum built up in them. Put it back together and it fired up and ran and accelerated a lot smoother but still had the pop. Ended up being tight exhaust valve. Had everything back together and it was running amazing!! Right up until it went to crap...Took off from a stop sign on a straight away and wound out 1st and 2nd pretty good when I shifted into 3rd I lost most of my power just like if I needed to flip over to reserve,but after I did I never regained power. After stopping and looking I still had plenty of gas. There were no noises or catastrophic mechanical problems. It was firing on the front cylinder but losing the rear cylinder when you revved past an idle...checked some things and tested some things and had all intention of upgrading the ignition system anyway so I decided this was a good time to do so...so since then I have put on Dynatek 3000 ignition and coils, new regulator/rectifier, new stator/pickup coil, and new Iridium plugs. I put them on one piece at a time trying to determine what the original problem was, but even after all of that it is still not firing properly on the rear cylinder. With a timing light inductive lead on the front plug wire it fires steady and regular, the rear cylinder is very erratic and all over the place. Is there anything else on these bikes that controls ignition that I might be missing?
2004 V-star 1100 Custom
Dynatek 3000 ignition
I was having the same problem but on my front. Bought some B12 carb cleaner (also works as starter fluid hehe) and took my carbs off again and went through them pretty good. My front carb had some nasty black crap in the air passage holes on the front of the carb. It runs great now and I replaced the plugs again while I was at it.
I am wondering if you aren't getting spark though to that cylinder. You can check it simple enough by pulling the plug out and connect the wire to it tap the spark plug threads to the frame and try to turn it over I recommend pulling both when doing this and just turning the gas to off so the bike doesn't try to turn over.
You will see an awesome little blue spark on the plug if good. Also use something to hold the plug other than your hand and make sure nothing flammable is around.
If no spark go back through your connections again and make sure the wires all good and not cracked or broken anywhere.
Also, if you have spark verify fuel is making it was down the fuel tube to that carb. I connect my compressor to the gas lines at the start of riding season and blow any junk through them on all my bikes just to make sure.
You said it was sitting for a while so you might as well toss a fuel filter on there as well just to eliminate that as well.
2007 V star 1100 Classic flat black bagger.
I did run wire thru all the holes on the jets and had it all cleaned and looking good. I flushed all the passages and blew them out with my air nozzle. I also pulled the plugs out and the front cylinder was steady and the rear one was spuratic...the new coils came with wires but you had to reuse the screw on plug boot..is there anyway those could be a problem? There doesn't really seem to be much that could go wrong with them, they both looked good and had no corrosion when I put them on. I am reasonably certain that the carbs are good because the rear plug was wet when I pulled it out so it is getting fuel, it just isn't firing like it should. But just for grits and shiggles I am going to pull the carbs back off this week and make sure everything still looks good with them.
I think I am surly posting in the wrong place. Sorry
I checked spark,coil,got -new spark pulgs-replacement coil. Rear had great spark. Front plug is good. Did the ohm test all coils( I have 3 now) tested fine.
When I check voltage on front coil with key on it is at 10 volts. The rear coil shows no volts with key on.
I am stumped.
I traced my problem to a bad cdi unit. How I was able to test was connect a ohm meter to the coil hot leg and then to bike ground. It showed a short. Then I disconnected the cdi and there was no short.
Bought a cdi and installed it yesterday and rode the bike today.
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