FraireRacing Posted May 12, 2013 Report Share Posted May 12, 2013 Here's a little of the set up that I have. I have a stock stroke crank, stock cyls that have the drag port with boyesen intake ports and triple exhaust, the cyls are at 66 bore and are decked, the piston comes out about .040 to .050 so I cut .030 on the domes of my cool head and it barely cleared. I have 1/4 in reed spacers with V force 2 reeds and an aluminum Y with a 39 PJ keihin carb. I have a .63 pilot and a main drilled out to 330 but I think I'm still running to lean. I have a k&n 7in pod. I'm running the NGK b8es plugs and as for ignition I have a Ricky stator with advance plate set at +4. My engine overheats quick and I have a oversized aluminum radiator and a pro design water pump impeller. Do I need a bigger carb or do I just need to go back to dual carb? Please let me know any advice you guys might have Quote Link to comment Share on other sites More sharing options...
Fastassbanshee96 Posted May 12, 2013 Report Share Posted May 12, 2013 You never said what the problem was besides you over heat fast. Quote Link to comment Share on other sites More sharing options...
RadarRacing Posted May 12, 2013 Report Share Posted May 12, 2013 You think you are running too lean? Because it is overheating? You have a mainjet drilled out to a size 330? This makes very little sense. You dont base jetting off motor temp and if motor temp becomes hot very quickly due to jetting you have problems. My guess is you now have your custom home cut domes that are making the motor very unhappy and have detonation problems regardless of how much fuel you put in it. Quote Link to comment Share on other sites More sharing options...
FraireRacing Posted May 12, 2013 Author Report Share Posted May 12, 2013 My engine pops while idle and while reving it. It has major low and mid lag and when it revs up to high rpm it picks front wheels of the ground. Two buddies of mine told me I was running to lean that it was the reason for the popping and the overheating. As far as the domes they were cut by a local machine shop Quote Link to comment Share on other sites More sharing options...
RadarRacing Posted May 12, 2013 Report Share Posted May 12, 2013 You havent stated what cc domes you have in it or fuel but honestly cutting the band to fix the too tight of squish effectively makes the dome/motor itself still have much higher compression than what the normal CC of the dome. If its lean you will know that by checking your plugs and doing what is referred to as a plug chop. Honestly I am not saying this in any way to be a dick but you need to learn to read plugs to check jetting and cutting the squish band on a dome will make the squishband wider and still have higher compression and trapped volume than what you would want. Try higher octane fuel if its on gas or pumpgas. Quote Link to comment Share on other sites More sharing options...
sheerider11 Posted May 12, 2013 Report Share Posted May 12, 2013 My engine pops while idle and while reving it. It has major low and mid lag and when it revs up to high rpm it picks front wheels of the ground. Two buddies of mine told me I was running to lean that it was the reason for the popping and the overheating. As far as the domes they were cut by a local machine shop What's the squish? Angle? CC? Quote Link to comment Share on other sites More sharing options...
FraireRacing Posted May 12, 2013 Author Report Share Posted May 12, 2013 The domes are 20cc and yes I know reading plugs they're white so unless I'm wrong what does that mean? Quote Link to comment Share on other sites More sharing options...
FraireRacing Posted May 12, 2013 Author Report Share Posted May 12, 2013 About the squish I have no idea of what that means? And I use 91oct pump gas Quote Link to comment Share on other sites More sharing options...
FraireRacing Posted May 12, 2013 Author Report Share Posted May 12, 2013 I was looking for a more of a brownish color for it to be good Quote Link to comment Share on other sites More sharing options...
FraireRacing Posted May 12, 2013 Author Report Share Posted May 12, 2013 Yes you read right it's cause I use it for both trail and drag trail every Sunday and drag once a month or every now and the at the dunes Quote Link to comment Share on other sites More sharing options...
FraireRacing Posted May 12, 2013 Author Report Share Posted May 12, 2013 I tried the set up back when I was first stating to do mods to it and loved it. Never really had issues with it till now so I got a bigger carb and this is where I'm at now lol Quote Link to comment Share on other sites More sharing options...
rdzbangshee Posted May 12, 2013 Report Share Posted May 12, 2013 Plastic impeller gear may be shot , I never run a plastic gear myself . Quote Link to comment Share on other sites More sharing options...
RadarRacing Posted May 13, 2013 Report Share Posted May 13, 2013 White plug = hugely lean. Keihin carbs do not use a size 330 mainjet. They are usually 165, 170 , 175 , 180. Mikunis are bigger numbers like 350, 370 Quote Link to comment Share on other sites More sharing options...
FraireRacing Posted May 13, 2013 Author Report Share Posted May 13, 2013 Yeah that's what they told me but I asked a guy hear who owns a local quad shop he said that keihin sells the drill bits to drill out the jets to a bigger size and he drilled mine out to a 330. And the keihin carbs are a lot bigger than munikis I was running two munikis with 420 and my 39pj with the 330 is better Quote Link to comment Share on other sites More sharing options...
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