RadarRacing

Gearing is too high for either of those bikes racing 10 miles.

10 mil cubs normal as cast porting is about 194/128 or 130.

X4 , a coolhead will give you a decent boost everywhere.

As stated in this thread it is possible to have too much fuel and oil not being burned and just sticking to the pistons. It depends on oil too. Its up to you to tune and decide which it is. http://bansheehq.com/forums/index.php?showtopic=130836

The carbon on pistons tells us alot about heat and jetting. That looks quite lean and hot. What you would like to see is whats called "piston wash" where fresh fuel will wash the tops of the pistons by the transfer ports and wash the carbon off out to about half way to the middle of the bore. The pistons would be best to have a fairly clean area by the transfers and be a little browner or blacker towards the center of the piston.

Thats not a slingshot. What brand is that? Gigot Performance sells the slingshot and it works fine with a pancake. Is that a vitos or somethin?

I wish I was coming but I cant make it happen. Be sure to post up plenty of videos so i can at least watch you guys havin fun.

That would mean ignition or preignition would occur too early and try to push the piston backwards some before the downstroke. Different builders do different things. Normally 17cc domes would be small for a 10mil cub. That doesnt mean they are but "normally". Also "normally" we would run 7-9 degrees of timing or more. If you arent showing any heat on the plugs that may keep it safe with the 17cc domes and if you crank up the timing or lean it down you may have detonation problems. Honestly you should CC the cylinders and check the true compression by measuring the trapped volume with the piston at TDC.

I dont know who dynoed this thing for you but 2 strokes will look lean till they hit the powerband on a dyno. That 16-1 afr at 40 mph actually IS lean for a second due to the dyno having a load on the motor , not revved , carbs wide open. That is normal but can scare the pants off a guy thats used to dynoing 4 strokes. What you wanna look at is when the bike starts revving. It appears rich on the needle but cleans up. If you get it tuned better the top graph will move farther to the right and not peak at 8,500. It will peak at a little higher rpm and your peak hp number will change slightly. It will actually show a little higher peak rpm and hp due to the pipe getting hot quicker too. If I had to guess its pretty rich on the needle.

It woukd be a ton of jet size difference. I have dual feeds on alky and can probably burn a half a gallon in a 300' pass if I have them wide open. They will suck a ton of fuel thru them wide open. Single feeds would probably be close to a jet size every 1/4 turn if I had to guess.

Has stretch marks. You guys like those alot.

They dont have a stock frame requirement on anything else thats stupid. Ever see a stock frame on a funny car , or a top fuel dragster. Yeah..dumb.

Wildcard or Andy at M/M Atv aka No limit Powersports. I know Andy keeps em in stock and has always got em right out.

If you let it warm up a few seconds and clean it out by revving it up a couple cracks of the throttle then when you hold the throttle about 1/4th- 1/3rd it should NOT blow alky all over your hand. If it does lean out your needles till it gets dry and pretty warm coming out.

If you would put where you are from in your profile someone close can maybe help. A good tuner can tell in about 30 seconds if you are rich on the needle and whether your plugs look rich. Honestly you wont have much sputtering or poor running from being too rich on the PJ. It will burn and run good even going thru a half gallon in a couple 300' passes. It kinda sounds like its just bogging out of the hole from being rich on the needle to me. It shouldnt blow tons of alky out of the pipes and need cleaned out a ton. If you dump the clutch... bluh,bluh, and then screams up top. If thats the case PJ adjustment will do nothing to change it. Its needle, pilot leaning you need.

5 1/4 or so on singles. My dual feeds are 6 if I remember right.

All good. I agree ^ ride it like it owes ya money.

Im sure meant 7 thous.

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

Haulers have worked for me at little sahara at 3 or 4 psi. Extremes about 3psi. It sometimes depends on the carcass of the tire. Many of the newer skattraks in the last 5 years or so are very square instead of crowned and have to have less air to work right. Even tho they will look flat and square.

That is a long hard pull on a motor. Make sure you have your float level set right but I dont know anyone that tries to do over 1/4 mile on stock carbs. Dont do that. Lol

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.

You can get .008 also and a few other thicknesses. Some .010 gaskets will smash down to .007 or .008. I dont know what gasket you are using right now or how much less squish clearance you need.

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.

Just run the right pistons and get the correct domes in a coolhead of he doesnt have one. That is all.