PhatRacing Posted November 22, 2003 Report Share Posted November 22, 2003 So, i get my carbs bored 2mm, get jets, a 280 main and a 35 pilot, (did have a 260 main and a 25 pilot, needle in the 5th position, and this was slightly lean for the cool fall weather in MI) and put it all together.... try to start it, and nothing.. no fire... not even a fart, so with a little persuasion i get it to start and its dead lean.. i mean it won't even run for 30 seconds, changed EVERYTHING.. it seems to run the best with the 260 mains and the 35 pilots.. needle in the 4th position still lean as hell, but at least it starts when you kick it. when you go up to the 280 main it gets even leaner which makes no sense at all to me, tried air screws in all kinds of positions from closed to open 2 turns.. i've been doing some reading and i'm pretty sure i need a much bigger main, something in the 300- 340 range, but i'd like some advice, it has; pro circuits, boysen reeds, spacers, twin k&n's (no airbox), .020 overbore, prolites, 2mm bored carbs. has anyone ever heard of drilling jets? when i look through the mains the 260 actually looks bigger... now its REALLY hard to tell, but i swear they're bigger... the previous owner re-jetted it when the pipes and reeds were done.. but since i've bought it i did the top end, carbs and k&n's... but i have no idea what he did exactly, it has 5n-7 needles in it, i haven't moved it up to the 5th position, i got tired of messin with it and its 4am... ANY help is appreciated, thanks, Andy 'Phat' Wirgau Quote Link to comment Share on other sites More sharing options...
Banchetta Posted November 22, 2003 Report Share Posted November 22, 2003 35 pilots will make it start hard. Why the hell would you want such a large pilot??? Go to a 30 pilot and start w/a 320 or 330 mains, needle in the 3rd or 4th clip fromt the top.... Quote Link to comment Share on other sites More sharing options...
PhatRacing Posted November 23, 2003 Author Report Share Posted November 23, 2003 ya but when i get it started mind you 35 pilots in it and 340 maiins and the needle jet is in the 5 position air screws are all the way in now it starts but its got an eratic idle and it revs out when i choke it with my hands it starts to cool off and run regarly i think honestly that i need bigger pilots it only makes sense dont it? i dont know i need some hella help here!~ Quote Link to comment Share on other sites More sharing options...
Banchetta Posted November 23, 2003 Report Share Posted November 23, 2003 Possibly the carbs might be plugged?? Not the jets, but the passageways...Try blowing them out w/ an air compressor....Did you make sure you put the little equalizer tube on between the carbs?? (1/4"x2"long). That sounds more like the problem...also make sure you have the slides in the right carbs. Cutaway in the slides should face the air box...Make sure you didn't mix the bowls on the carbs...One of the bowls on the bottom of the carbs has a brass tube for the choke. If you swap the bowls, then the choke won't work right....That'll get you started.... Quote Link to comment Share on other sites More sharing options...
teamriot Posted November 23, 2003 Report Share Posted November 23, 2003 HOW CAN YOU TELL WHICH BOWL GOES WHERE? IS THERE A VISUAL DIFFERENCE? OR MAKING? THANKS Quote Link to comment Share on other sites More sharing options...
chrome112 Posted November 23, 2003 Report Share Posted November 23, 2003 possible air leak, also your pilots are huge, but people have allready todl you that. Quote Link to comment Share on other sites More sharing options...
Banchetta Posted November 23, 2003 Report Share Posted November 23, 2003 HOW CAN YOU TELL WHICH BOWL GOES WHERE? IS THERE A VISUAL DIFFERENCE? OR MAKING? THANKS One bowl has a little jet and brass tube..the other doesn't... Quote Link to comment Share on other sites More sharing options...
PhatRacing Posted November 24, 2003 Author Report Share Posted November 24, 2003 ok i checked the bowls and is the one with the needle jet suppose to go in the one with the choke or the other one and yes i do have the equilizer tube in place and i blew out all the orfices also did compression test and air leak down test everything is kosher there too. it all commes down to the idle its lean at idle once i get it past 1/8 throtle its ok and it throws smoke and revs quick but at idle is were my main problem is. i apperciate all your help banchetta got any other ideas?????? thanks ill be watin for more info i am cheking this forum on the hour!!!~~~~~~~ thanks, phat andy~ Quote Link to comment Share on other sites More sharing options...
Banchetta Posted November 25, 2003 Report Share Posted November 25, 2003 Ok heres the deal. The mains have absolutely NO control over idle. ONLY wide open throttle and thats it..To dial them in, run it wide open in 6th gear for 5-10 seconds and shut it down, coast to a stop and pull the plugs, tan or white is lean, brown is perfect, black is rich...I'd start w/ a 300-320 mains and go from there.... Your needles ONLY control 1/4-3/4 throttle. You can find the best position just by trying different positons and feel the difference by seat of the pants feel...I notice stronger pull at lower rpms and powerband kicking in sooner and at lower rpms... Next is your pilots and air screws which both control idle and throttle response. The air screws fine tune the pilots...A rich pilot will usually start easy when cold but starts hard when warm, you'll also have to keep revving the shee to Clean it out.. A lean pilot will start hard when cold and even warm...It'll also cause a great hesitation at off idle... W/ that being said, I have a couple of other q's for you...How did it run w/ the stock pilots?? How do you clean the K&N's?? What kind of cleaner you use? Do you still have the stock carb tops?? Quote Link to comment Share on other sites More sharing options...
PhatRacing Posted November 25, 2003 Author Report Share Posted November 25, 2003 the k&n's are brand new, factory oiled, it still has the stock carb tops, the tors wires have been cut and twisted together. the bike doesn't start cold without ether or gas squirted in the carb, it idles up and down but always high, and its starts hard as hell if at all when its warm. when you get it warm and gas it it runs fine.. and it'll idle high as hell when its warm, bogs just off idle, you play with it a little and get some r's and it cleans up and runs perfect... if not a little rich.. the airscrews are turned all the way in, if you turn them out it gets worse, it won't idle or rev once you get it running, it runs out of gas... i still think i need a bigger pilot... i'm going to take them apart and go over them with afine tooth comb and look for shavings or something stuck in the passages.. thats the only thing i can think of that might be happening. Andy Quote Link to comment Share on other sites More sharing options...
Banchetta Posted November 25, 2003 Report Share Posted November 25, 2003 Sounds like an air leak....Is there a gasket on the carb tops around the spring?? An erratic idle and high rev means there is some kind of air leak....I'm trying to wonder if boring the carbs messed something up or maybe the slides don't close up enough.....maybe metal filings jammed in the passageway...I don't think its a fuel problem, but an air leak....High revs is not caused by leanness, but by the motor getting more air to rev up....remember, the motor is an air pump, the carbs cutting off the air is what idles the motor, open the slides and it'll rev....an air leak will make it rev allowing the motor more air......you have an air leak somewhere...make sure your slides are in the right carbs....cutaway facing the intake.. Quote Link to comment Share on other sites More sharing options...
azsandrat Posted November 25, 2003 Report Share Posted November 25, 2003 ARE YOU SURE THE SLIDES ARE IN THE RIGHT WAY. RADIUS TO THE REAR OR TO THE AIR CLEANER. KINDA SOUNDS LIKE AND AIR LEAK TO ME TOO. BANCHETTA'S PRETTY GOOD AT DIAGNOSING . GOOD LUCK Quote Link to comment Share on other sites More sharing options...
PhatRacing Posted November 25, 2003 Author Report Share Posted November 25, 2003 carb cut awaay is to the intake side i know that thats not it. but what does the little holes in the throat there in the back to little tiny holes if those were pluged would it starve for fuel?? becasue when i choke it with my hands and it gets more gas than air it idles down but then when i take my hands away and it gets more air it revs up and dies like its runing out if fuel at idle~~~~~~~~~well any ways i got sick and tired of it tonight so i played with my nitro car hehe took my mind off it for a while well im going to hit it up again! tomorrow thanks again banchetta appreicate all your help so far....... phat andy~ Quote Link to comment Share on other sites More sharing options...
Banchetta Posted November 25, 2003 Report Share Posted November 25, 2003 Those holes are for air..One goes to the air screw..Idling high means your shee likes the mixture better...You want a better mixture and higher rev from the mixture, then turn the idle knobs down to compensate...I usually take a flashlight and look into the intake. Turn the idle knobs so the slides drop all the way down and barely "bottom out" then turn the idle knob one full turn back up. Do this to both sides and you'll be synced. The idle should be very close also, and within 1/4 turn on the idle knobs....I still think the larger pilots aren't helping and I'd drop to the stock pilots or 27.5 and go from there.....but I could be wrong also... only a suggestion.. Quote Link to comment Share on other sites More sharing options...
itsaripper Posted November 25, 2003 Report Share Posted November 25, 2003 Did you have the carbs bored strait through, or taper-bored? I measured my slides and get 1.079in converted to mm 27.38. If the bore is 28 you may have too much room on the sides of the slides, which will lean your mix out. When you put your finger over the intake you restrickt the air and that brings air-gas mix more in line with what it should be, and so it idles back. You shouldn't need to run over 27.5 on the pilots and 320 on the mains. Quote Link to comment Share on other sites More sharing options...
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