frankO 7 Posted April 25, 2011 Report Posted April 25, 2011 Hey guys... my left cylinder is not firing right at all... and sometimes not firing at all. This started at the very end of last season so i thought the carbs just needed to be cleaned. Last season the bike was all stock except pipes and silencers with 230 main jets, the rest of the carbs were stock set up. It has ran great at this set up for a few years now. I put it up for the winter and tore the carbs down for a good cleaning this spring and also made some additions to the quad. Here is a run down of my set up... -all stock motor and carbs (2002) -Pro Circuit pipes and silencers 304 seriers -1200ft elevation -310 mains, 25 pilot, stock needle in 3rd clip down -Bosen dual stage power reeds -k&n air filter in box with k&n power lid -yamalube pre-mix at 40:1 -Compression at 115 in both cylinders -BR8ES plugs -TORS removal kit by Vito's Today i finished all of these mods and started it up. It fired right up and I set the idle and it was running strong on both cylinders. I let it idle for at least 10 min with some revs here and there and everything seemed fine. Then the left cylinder started to cut out once it got warmed up. I switched the plug wires to see if it was a bad wire and still the left cuts out. I set the left plug on the head and it is getting spark. Now it seems the left cylinder isn't really firing at all... just blowing some exhaust thats being produced by the right cylinder. I don't know WTF the deal is now. Electrical problem?? Is my left cylinder blown? When i looked in through the port holes the cylinder walls and pistons looked good with little to no scratches. Any help would be appreciated! Quote
sangheraent Posted April 25, 2011 Report Posted April 25, 2011 did you try swapping the plugs? sounds like a fouled plug to me. Quote
frankO 7 Posted April 25, 2011 Author Report Posted April 25, 2011 did you try swapping the plugs? sounds like a fouled plug to me. I put new plugs in at the end of last season when it first started to see it that was the problem and it still did the same thing. I swapped these plugs around too and still the same... Quote
sangheraent Posted April 25, 2011 Report Posted April 25, 2011 I put new plugs in at the end of last season when it first started to see it that was the problem and it still did the same thing. I swapped these plugs around too and still the same... if you swapped the coil and plugs around and it was the same cylinder then you know its not electrical. my banshee did this to me and it turned out the glass on the right side carb had popped out and was just leaning out like crasy. look for an air leak. also check your compression. check the obvious first, is there anything wrong with the intake boots, exhaust seal?, airbox boots? if those all clear the inspection then go into the carb and make sure its 100%. Quote
frankO 7 Posted April 25, 2011 Author Report Posted April 25, 2011 if you swapped the coil and plugs around and it was the same cylinder then you know its not electrical. my banshee did this to me and it turned out the glass on the right side carb had popped out and was just leaning out like crasy. look for an air leak. also check your compression. check the obvious first, is there anything wrong with the intake boots, exhaust seal?, airbox boots? if those all clear the inspection then go into the carb and make sure its 100%. Everything looks perfect but obviously something is still wrong... I just got done going through the carbs, had them totally disassembled and everything looked perfect and it's still running the same. All intake and airbox boots are in great shape, just cleaned them. New float bowl/reed cage gaskets and all exhaust seals too. No exhaust or air leaks that i can find... All hoses and lines in the proper locations. Just put a new plug in a few minutes ago and still the same. The cylinder will fire and rev like normal for the first few seconds then just dies out. It''s getting gas to the plug... idk... i don't get it. I've went down all of the obvious avenues... compression in both cylinders was at 115 today. When i first started it today after finishing the mods i mentioned in my first post both cylinders ran great for the first 10 min or so then the left cylinder started to die out. Now every time i start it up it only runs on the left for a few seconds... WTF?? Quote
sangheraent Posted April 25, 2011 Report Posted April 25, 2011 did you try to swap the carbs from side to side? if you swap the carbs and it is still doing it The problem is mostly likely the reeds. inspect to make sure there isnt anything stuck in them or there not installed incorrectly. Quote
ban565 Posted April 25, 2011 Report Posted April 25, 2011 If you had the pipes off look to make sure that something is not plugging up the left side pipe. It happen a buddy of mine. Quote
frankO 7 Posted April 25, 2011 Author Report Posted April 25, 2011 The carb swap is a great idea to help diagnose the problem! Didn't really think of that since they're side specific... nice call! I'm kind of ruling out the reeds and something stuck inside the motor because this started with the old reeds which were in good shape and I just put in new ones. I also had the ports stuffed with clean rags and accounted for them after install. But at this point, if the carb swap fails, i'm going to double check everything just to make sure. Thanks guys! I'll let you know. Quote
Larry's Shee Posted April 26, 2011 Report Posted April 26, 2011 (edited) If you had the pipes off look to make sure that something is not plugging up the left side pipe. It happen a buddy of mine. This very thing just happened to me. A mouse built a nest with fiberglass insulation/packing in the pipe!! If you carb swap don't foget to get a long choke crossover tube !! Edited April 26, 2011 by Larry's Shee Quote
sleeper06 Posted April 26, 2011 Report Posted April 26, 2011 or floats arnt working properly slow fill when you let it sit it will run off the bowls but sucks it dry quick Quote
frankO 7 Posted April 27, 2011 Author Report Posted April 27, 2011 alright... did the carb swap but it wont start at all. Is this because i dont have the choke crossover tube hooked up? Haven't found one long enough yet to see for sure... I'm starting to think about the float not working properly and sucking the gas in the bowl dry like dude above said but idk. I know the float is not stuck... how do you find out if its sucking the bowl dry? Why would it all of the sudden not be getting gas and/or sucking the bowl dry? I know the lines are clear and gas is flowing... This kind of makes sense because it was running fine at first and then kind of dies out like its not getting gas on the left cylinder. But then again im pretty positive that the plug had gas on it when i took it out. well idk. gonna go drink myself into a drunkin stupor... Any comments would be appreciated! Quote
Jereme6655 Posted April 27, 2011 Report Posted April 27, 2011 hey frank.....this might sound odd....but just humor me.....you've changed alot of stuff on your bike over the winter that have to deal with air/fuel. Were the pro circuits always what you ruan or are they different than the ones you used to have on your bike. ALSO......running pipes you should increase your pilot jet size up to help handle the larger required amount of fuel at low-end. you might just be restricting it so much that its cutting out a cylinder. AND its a VERY cheap fix if it is the problem... Quote
Larry's Shee Posted April 27, 2011 Report Posted April 27, 2011 Like I posted you need the tube. There is a possibility that the float closes when bowl is full , opens enough to fill bowl when not running, but doesn't open fully to meet demands. Also check that the vents on carb are clear, either blow air thru it or suck on hose to be sure it's open. Quote
sangheraent Posted April 27, 2011 Report Posted April 27, 2011 run down to the hardware store and pick up some clear hose for a buck or what not and try the carbs. Iv had my floats run dry and usually the bike will idle just fine as soon as I gave the gas the one cylinder shut down. Quote
frankO 7 Posted April 28, 2011 Author Report Posted April 28, 2011 The pro circuits are same pipes i've ran for the last 3 years or so... So i found an old gas vent tube and did the carb swap... its a problem with the carb. The right cylinder cut out just the same as the left when i switched them out. So i took the carbs out, through size 30 pilots in both carbs and adjusted the adjust tang on the float in the left carb to allow more fuel to enter. Still the same deal... not firing barely at all on the left side. Maybe i need to adjust the tang a little more? lol... When i first removed the carbs it was obvious that the carb that is giving me problems had barely any fuel in it compared to the good working carb. When i measured the float height in both carbs they appeared dead even. This problem started with the same set up i was running for a few years so it seems odd to me that all of the sudden the bowl on one carb is being sucked dry. And them still the same problem after all the upgrades and cleaning. Is adjusting the tang the way to try and fix this problem?? I'm pretty sure i lowered the float height to allow more fuel to enter. Maybe i did it backwards? Or just maybe not enough? Or just maybe i'm going to beat the shit out of my carb!! 1 Quote
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