252wheelieking Posted June 30, 2010 Report Share Posted June 30, 2010 I need help badly....I have basically a stock motor. It starts first kick everytime & idles perfect. It takes off fine with no bogging or nothing. A perfect bottom end, but its when I get to about a 1/4 throttle thru W.O.T. It sputters, break up, spit back, backfire, & has no power at all. I know its the jetting, but I dont have a clue to what size larger main jet to start with. It will only run 69-70mph the way it is now with a 1/8-1/4 throttle. I checked for air leaks & the motor is tight. My setup is: Coolhead w/21cc domes Wiseco pro lite pistons V-F 2's reeds (reeds are new) Boss Racing intake w/ built in crossver tube 34mm Keihin PJ carbs (#55 pilots / #152 mains Dual K&N filters w/ airbox removed adjustable timing plate @ 0 degrees(stock) RM Stator (stator) RM Stator adjustable CDI box 16T-40T sprocket gearing Quote Link to comment Share on other sites More sharing options...
pr0blumz Posted July 1, 2010 Report Share Posted July 1, 2010 I need help badly....I have basically a stock motor. It starts first kick everytime & idles perfect. It takes off fine with no bogging or nothing. A perfect bottom end, but its when I get to about a 1/4 throttle thru W.O.T. It sputters, break up, spit back, backfire, & has no power at all. I know its the jetting, but I dont have a clue to what size larger main jet to start with. It will only run 69-70mph the way it is now with a 1/8-1/4 throttle. I checked for air leaks & the motor is tight. My setup is: Coolhead w/21cc domes Wiseco pro lite pistons V-F 2's reeds (reeds are new) Boss Racing intake w/ built in crossver tube 34mm Keihin PJ carbs (#55 pilots / #152 mains Dual K&N filters w/ airbox removed adjustable timing plate @ 0 degrees(stock) RM Stator (stator) RM Stator adjustable CDI box 16T-40T sprocket gearing Test your coil and stator. Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted July 1, 2010 Report Share Posted July 1, 2010 What needles are you running? Quote Link to comment Share on other sites More sharing options...
252wheelieking Posted July 1, 2010 Author Report Share Posted July 1, 2010 What needles are you running? The standard needles that came in them (48CEG needles)........I need help badly.....I checked my plugs yesterday & they are dark, which from my understanding im running too rich on the pilot jet. My pilot is a #55...@ 1.5 turns out. Both of my cousins are killing me. One have a Honda 450r(piped & jetted) & the other one has a Raptor 660(piped & jetted). Leaving the line I smoke'em everytime thru the gears @ 1/8-1/4 throttle, but top side them 4strokes making me look bad. Quote Link to comment Share on other sites More sharing options...
252wheelieking Posted July 1, 2010 Author Report Share Posted July 1, 2010 Test your coil and stator. The coil & stator checked out fine. I switched them with my cousins banshee & worked perfectly. Quote Link to comment Share on other sites More sharing options...
252wheelieking Posted July 1, 2010 Author Report Share Posted July 1, 2010 Test your coil and stator. The coil & stator checked out fine. I switched them with my cousins banshee & worked perfectly. I noticed oil around the top of the domes on both sides where the spark plug are. What could that be? looks like an air leak! Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted July 2, 2010 Report Share Posted July 2, 2010 I would say that your plugs are black due to the 55 pilot, and since you have been riding at under 1/4 throttle your riding on or around the pilot jet. I would try CEK needles. You have CGL's. CEK's work pretty good in pj's. They are a shorter needle. Since your all the way rich on the needle now you need to install a shorter needle and reinstall them in the middle clip. They both have the same taper, but the CEK's will be a little richer around 1/4 throttle because they are a smaller diameter. Quote Link to comment Share on other sites More sharing options...
cactusted Posted July 2, 2010 Report Share Posted July 2, 2010 Welcome to PJ carbs. Mine drove me nuts until I dialed them in. It's impossible for any of us to give the absolute fix but here are a few things to check. Go for the easy adjust no money items 1st. Check your choke. On the PJ's your choke is your only fuel/air adjustment. Clockwise is more air. If all the way counter clockwise then try turning clockwise to increase your air at idle. I mark mine with white-out so I can turn them equally. See if it makes a diff on your black plugs. Most likely you need to drop a size or 2 on your pilot though. Do 1 thing at a time. Even though the Pilot/Needle & Main are diff circuits they do affect the next circuit. Once your idle seems good (steady), try lowering your needle clip 1 position. This will increase your fuel from 1/4 to 3/4ish. If better but still sputtering, raise again. If still no good then you may need to go to a shorter or thinner tapered needle. You can find a needle chart on Sudco's website in their parts pdf catalog. I would only do this after your pilot is dialed in because it does affect the mid throttle too. Once pilot & needle are set, then address your main. Sputtering = too lean & bog = too rich. Once all is dialed in, use your choke/air/fuel knobs to fine tune for idle for minor elevation & temperature changes. Obviously before any of this, check for: air leaks, float height & unclogged jets 1st. Hope this helps. Quote Link to comment Share on other sites More sharing options...
252wheelieking Posted July 3, 2010 Author Report Share Posted July 3, 2010 Welcome to PJ carbs. Mine drove me nuts until I dialed them in. It's impossible for any of us to give the absolute fix but here are a few things to check. Go for the easy adjust no money items 1st. Check your choke. On the PJ's your choke is your only fuel/air adjustment. Clockwise is more air. If all the way counter clockwise then try turning clockwise to increase your air at idle. I mark mine with white-out so I can turn them equally. See if it makes a diff on your black plugs. Most likely you need to drop a size or 2 on your pilot though. Do 1 thing at a time. Even though the Pilot/Needle & Main are diff circuits they do affect the next circuit. Once your idle seems good (steady), try lowering your needle clip 1 position. This will increase your fuel from 1/4 to 3/4ish. If better but still sputtering, raise again. If still no good then you may need to go to a shorter or thinner tapered needle. You can find a needle chart on Sudco's website in their parts pdf catalog. I would only do this after your pilot is dialed in because it does affect the mid throttle too. Once pilot & needle are set, then address your main. Sputtering = too lean & bog = too rich. Once all is dialed in, use your choke/air/fuel knobs to fine tune for idle for minor elevation & temperature changes. Obviously before any of this, check for: air leaks, float height & unclogged jets 1st. Hope this helps. How do I remove the needles from the PJ slides? Quote Link to comment Share on other sites More sharing options...
wesw Posted July 4, 2010 Report Share Posted July 4, 2010 6mm socket or needle nose pliers to take the slides apart. ceg is a rich needle down low and 55 pilot is huge for a stock motor you need to be working a leaner pilot or a different needle Quote Link to comment Share on other sites More sharing options...
252wheelieking Posted November 20, 2010 Author Report Share Posted November 20, 2010 6mm socket or needle nose pliers to take the slides apart. ceg is a rich needle down low and 55 pilot is huge for a stock motor you need to be working a leaner pilot or a different needle Come to find out that the CDI box from RM Stator was the problem the whole time.....it limited my RPM's badly....I installed my cousins whole electrical system & it open right up....now the jetting is rich....but since then I done got a new stock CDI box, HJR dune port & T5's, it's still rich. Im just gonna work my way down on the pilot until it looks closer to a caramel color. How long do I have to ride the bike to get a complete reading on new plugs for different throttle postion's before the plug chop? Quote Link to comment Share on other sites More sharing options...
rdzbangshee Posted November 20, 2010 Report Share Posted November 20, 2010 i always check my plugs some time after two hours of good running they go out some times i take note over the condition and adjust but I'm fine if i run a jet or needle riche. and a cgk meedle is longer than a cek like running it on the 2rd clip Quote Link to comment Share on other sites More sharing options...
Larry's Shee Posted November 20, 2010 Report Share Posted November 20, 2010 Damn ,more RM junk !! Go figure Quote Link to comment Share on other sites More sharing options...
tesman123 Posted July 31, 2013 Report Share Posted July 31, 2013 i have an 89 banshee with a fresh bore[ about 10 hrs on it ] 30 over wiseco pistons, cool head with 20 domes, v-force 3 reeds, 34mm pjs, and full fmf exhaust. the problem im having is from idle to half to three quarter throttle it bogs and breaks up bad. i have to clutch it to get the rpms up then it flies. it sucks having no bottom end at all. i think its a 160 main and a 55 or 60 pilot with the pin that came with the carbs. im also running the stock air box with a k@n filter. and i have the individual filters also but seemed to suck to much air. if anyone has any advice that would be great....thank you.... Quote Link to comment Share on other sites More sharing options...
tesman123 Posted July 31, 2013 Report Share Posted July 31, 2013 i am running a 160 main and a 50 pilot... Quote Link to comment Share on other sites More sharing options...
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