jd250r Posted November 9, 2011 Report Share Posted November 9, 2011 (edited) Im having issue getting my bike jetted with 28mm pwks and a chariot intake. I have Pro Circuit pipes, stock air box with pro-flow and k&n and the previous owner said the head had been milled. Im at 2800ft elevation. I had stock carbs before that ran perfect. I started with 155 mains and new plugs, way lean. You could feel it when it hit the powerband that it was starving for fuel. So i went 165 mains and other set of plugs. Runs great all the way through the power band until the top of each gear then goes flat. Did another plug check still lean. Im now at 170 mains and still am having the same result. Its starts right up and idles perfect and runs great on the low-end side. According to everyone else with similar mods in the "jetting sticky" above, 170 seems way big. I have clear fuel line so I can see the fuel flow. Sitting at stop and revving it, it keeps the lines full. Could I be running dry on fuel going through the gears or do I need to step up the mains even more?? Any help would be very helpful! Edited November 9, 2011 by jd250r Quote Link to comment Share on other sites More sharing options...
Coupelx Posted November 9, 2011 Report Share Posted November 9, 2011 Im having issue getting my bike jetted with 28mm pwks and a chariot intake. I have Pro Circuit pipes, stock air box with pro-flow and k&n and the previous owner said the head had been milled. Im at 2800ft elevation. I had stock carbs before that ran perfect. I started with 155 mains and new plugs, way lean. You could feel it when it hit the powerband that it was starving for fuel. So i went 165 mains and other set of plugs. Runs great all the way through the power band until the top of each gear then goes flat. Did another plug check still lean. Im now at 170 mains and still am having the same result. Its starts right up and idles perfect and runs great on the low-end side. According to everyone else with similar mods in the "jetting sticky" above, 170 seems way big. I have clear fuel line so I can see the fuel flow. Sitting at stop and revving it, it keeps the lines full. Could I be running dry on fuel going through the gears or do I need to step up the mains even more?? Any help would be very helpful! sounds like you have an air leak. im at 140 mains on my 28pwks with ported cylinders and r2 pipes. Quote Link to comment Share on other sites More sharing options...
jd250r Posted November 9, 2011 Author Report Share Posted November 9, 2011 I was kinda thinking that also but wasnt sure. Is there any good way to test for an air leak?? Quote Link to comment Share on other sites More sharing options...
Surfrjag Posted November 9, 2011 Report Share Posted November 9, 2011 go ahead and do the leakdown test but it sounds like your actually rich on the mains to me. i have similar setup at sea level with 155's. with your elevation you should be leaner than me. also double check your float height. it should be 19mm Quote Link to comment Share on other sites More sharing options...
Zwiser Posted November 9, 2011 Report Share Posted November 9, 2011 im runnig t4 pipes with the pro flow kit with the lid on and im at 48 pilots, 148 mains Quote Link to comment Share on other sites More sharing options...
jd250r Posted November 9, 2011 Author Report Share Posted November 9, 2011 I think I am way to rich also but my plug keeps coming out very very light in color. Thats after i let it warm up, run it through the gears then hold 4th pinned for a ways then shut the engine off while pinned. I read just the leak down how-to. Ill try that tomorrw and see what happens. Illl check the float height now. This is driving me nuts, Im ready to put my stock carbs back on! Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted November 9, 2011 Report Share Posted November 9, 2011 I would say you have an air leak. That is the only reason you'd be up to 170 mains. I would stop riding the bike for sure. To check for an air leak, get some carb cleaner. Let the bike idle. Spray all around the engine and listen for the idle to come down. Keep checking spots until you find the air leak. The carb cleaner will act as a plug briefly. DO NOT use starting fluid. Quote Link to comment Share on other sites More sharing options...
jd250r Posted November 9, 2011 Author Report Share Posted November 9, 2011 (edited) Im not riding it anymore till I get it figured out. Ill try the carb cleaner and check float height tomorrow and report back. Thanks guys! Trying to make it to the dunes this weekend and Im losing hope! Edited November 9, 2011 by jd250r Quote Link to comment Share on other sites More sharing options...
jd250r Posted November 9, 2011 Author Report Share Posted November 9, 2011 Just been doing some thinking and I could be completely wrong, but wouldnt an air leak some where cause it to be hard to start or have an irractic idle? Its starts right up an idles perfect. I have a Chariot billet intake with built-in cross-over. Would the leak be some where in that since both cylinders are lean and have an almost identical plug reading? Just trying to think of all the possiblities that it could be. Quote Link to comment Share on other sites More sharing options...
SandSlingerOR Posted November 9, 2011 Report Share Posted November 9, 2011 Dont give up on the 28's you will love them. Mine tuned out way easier then the stockers could ever dream of, I bet you have a air leak as well. Quote Link to comment Share on other sites More sharing options...
jd250r Posted November 10, 2011 Author Report Share Posted November 10, 2011 Did the carb cleaner trick, sprayed all around the intake, head and base gaskets and heard no noticable change in the idle. Boisebanshee mentioned he had trouble with a lean condition with this intake and carbs and found it to be the two small screws on the back side of the chariot intake. I took the intake off and apart. Resealed everything and the screws. Tried it agian, no change. Going to check the float height now, maybe im running the bowls dry? Im to the point where Im completely lost. Might throw the stockers back on and see how it runs, if it runs good, then i know its in the intake or carbs. Im ready to throw in the towel. Quote Link to comment Share on other sites More sharing options...
jd250r Posted November 10, 2011 Author Report Share Posted November 10, 2011 Ok, checke float height with the needle seated and the float just touching the vavle pin. I was at 22.5mm give or take. I adjust both to 19mm. Now I have fuel running out the over flow tubes. . . . . Quote Link to comment Share on other sites More sharing options...
muggzy Posted November 10, 2011 Report Share Posted November 10, 2011 (edited) I just got a set of PWK28s myself so I'm really curious to see where this goes. Correct me if I'm wrong (anybody) on any of when I'm comanting on below here... I think I am way to rich also but my plug keeps coming out very very light in color. Thats after i let it warm up, run it through the gears then hold 4th pinned for a ways then shut the engine off while pinned. I read just the leak down how-to. Ill try that tomorrw and see what happens. Illl check the float height now. This is driving me nuts, Im ready to put my stock carbs back on! I've always gone up to 6th hold til max speed, then pull in the clutch and kill it. Never heard of only going to fourth. Maybe the lean reading isn't accurate? Ok, checke float height with the needle seated and the float just touching the vavle pin. I was at 22.5mm give or take. I adjust both to 19mm. Now I have fuel running out the over flow tubes. . . . . Need new float valves? the float height should be checked without full float pressure on the needle - sort of with the float hanging at a little less than vertical if you know what I mean? Body should start vertical and then tilt it down 'til the float just starts to press against the needle? Edited November 10, 2011 by muggzy Quote Link to comment Share on other sites More sharing options...
jd250r Posted November 10, 2011 Author Report Share Posted November 10, 2011 Ok got the floats adjusted agian to 19.2mm and 19.1mm. Went and rode it a bit. Felt good, the flat spot is no longer there so I thought I might have gotten it. Put a set of new plugs in it and ran it again. 4th pinned for a ways and shut it off. Pulled the plugs and they are still very very very light tan, more of a whitish then tan. Quote Link to comment Share on other sites More sharing options...
jd250r Posted November 10, 2011 Author Report Share Posted November 10, 2011 I dont have much room to get in over 4th pinned. Ive done it this way with my 250rs and have always had good luck. Quote Link to comment Share on other sites More sharing options...
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