crewchief3285 Posted September 24, 2006 Report Posted September 24, 2006 first i am at sea level ,390 mains ,30 pilots,40/1 mixture,and plug still reads lean, i cant get the it to lanch (pavement) it revs good put as soon as the clutch is out bogs for a sec then goes and pulls good . NEW MODS ARE noss head,21 cc domes,comp.150, ported stock cyl. boysen rad reeds, stock gearing 14/41. 22/11/9 tires. the plug looks a pinkish color.any help welcome . it does good on dirt but still reads lean.the exhaust tips on my t5s, are dry .possibly wrong mixture u think. :biggrin: Quote
2003LimitedBanshee Posted September 24, 2006 Report Posted September 24, 2006 Needle position? Revving under no load tells you little to nothing. The pilot is probably pretty close, maybe a bit big, but you didn't mention where your air screws are set. If your plugs are reading lean, have you checked for air leaks? What "style" porting do you have... drag, dune, woods etc? Temperature? The main might be a little small, but I wouldn't guess a bunch depending on what some of the answers to the other questions are. A bog down low would direct me to the pilot or needle circuit depending on what RPM range showed the bog. BUT, address the main jetting first as it will play a minor role in changing even your low RPM jetting. Hoepfully this give us a direction to work from. Quote
crewchief3285 Posted September 25, 2006 Author Report Posted September 25, 2006 Needle position? Revving under no load tells you little to nothing. The pilot is probably pretty close, maybe a bit big, but you didn't mention where your air screws are set. If your plugs are reading lean, have you checked for air leaks? What "style" porting do you have... drag, dune, woods etc? Temperature? The main might be a little small, but I wouldn't guess a bunch depending on what some of the answers to the other questions are. A bog down low would direct me to the pilot or needle circuit depending on what RPM range showed the bog. BUT, address the main jetting first as it will play a minor role in changing even your low RPM jetting. Hoepfully this give us a direction to work from. the needle is a dyno jet needle set at the 5th groove and the temp is 90 deg the bog is trying to lanuch the bike the porting is drag poriting the needle is a dyno jet needle set at the 5th groove and the temp is 90 deg the bog is trying to lanuch the bike the porting is drag poriting sorry also the idle screws are at 1.5 turns it just seems like a lot of jet but the plug tells all also the bike idles good wouldnt an air leak cause it not to idle correctly .its got good thrrotle response the bikes pulls hard but just wont launch. Quote
BANSHEEMANIAC Posted September 28, 2006 Report Posted September 28, 2006 where is the plugs reading lean at? are you riding wide open, or, are you holding it low and then cheaking the plugs? Quote
dajogejr Posted September 28, 2006 Report Posted September 28, 2006 wouldnt an air leak cause it not to idle correctly .its got good thrrotle response the bikes pulls hard but just wont launch. Nope...not at all. My cub motor had the grand canyon of air leaks between the base and cylinder, and it idled and started perfectly. Once it warmed up...the idle would raise 200 or so RPM for no reason, but...it idled great....never stalled. Double check for an air leak, but....if it revs out good, it's probably something else. Try a smaller pilot first, 27.5... I think you're a little rich on the needle...try the 4 clip from the blunt end... Quote
crewchief3285 Posted September 29, 2006 Author Report Posted September 29, 2006 where is the plugs reading lean at? are you riding wide open, or, are you holding it low and then cheaking the plugs? first i run it through the gears i shut it off and pull the plug Quote
crewchief3285 Posted September 29, 2006 Author Report Posted September 29, 2006 Nope...not at all. My cub motor had the grand canyon of air leaks between the base and cylinder, and it idled and started perfectly. Once it warmed up...the idle would raise 200 or so RPM for no reason, but...it idled great....never stalled. Double check for an air leak, but....if it revs out good, it's probably something else. Try a smaller pilot first, 27.5... I think you're a little rich on the needle...try the 4 clip from the blunt end... well ive moved the needle 2 the 4th clip same thing also forget the pipes get really hot they didnt before the porting i also put a 420 jet ,took all the packing outof the pipes no diff. i sprayed carb cleaner everywhere but all look good dont know . thinking of putting back the stock cyl. OH CUB WHERE ARE YOU. LOL. :: Quote
dajogejr Posted September 29, 2006 Report Posted September 29, 2006 Why would you pull the packing from the pipes? They're designed to run with it... Can you post a pic of your plug chop with the 390's in? Quote
crewchief3285 Posted September 29, 2006 Author Report Posted September 29, 2006 Why would you pull the packing from the pipes? They're designed to run with it... Can you post a pic of your plug chop with the 390's in? I DONT HAVE a pic or the plugs any more thrash but they were pinkish with some grey the packing was removed because 1 they told me the might be clouged since i bought them used and i was going to replace any way in fact orderd today.it pull good but just wont lanuch pavement, dirt spins the hell out of the tires, Quote
crewchief3285 Posted October 3, 2006 Author Report Posted October 3, 2006 was told to get a 35 or 40 piolt and a 420 or 440 jet what do you think right know have a 30 p/ and a 420 jet t5s are very hot thanks for your help Quote
dajogejr Posted October 3, 2006 Report Posted October 3, 2006 30 pilot should be fine. 32.5 is the max you'd need...but, you're only using the pilot circuit/air screw from idle to 1/8 throttle or so. Unless you're launching the quad at idle, the pilot circuit isn't your problem. Quote
crewchief3285 Posted November 13, 2006 Author Report Posted November 13, 2006 30 pilot should be fine. 32.5 is the max you'd need...but, you're only using the pilot circuit/air screw from idle to 1/8 throttle or so. Unless you're launching the quad at idle, the pilot circuit isn't your problem. FINALLY got it right threw out those stock cyl and crank put in a 4 mil with cubs enough said :beer: now what carbs and diffrent exhaust Quote
dajogejr Posted November 13, 2006 Report Posted November 13, 2006 Whooaaa....blast from the past... Depends on how you want to make your power. First off, stock timing or advanced? How much compression? As I'm sure you're aware....they have all kinds of top end power. If you want to dune more than drag race, get CPI pipes and 35 PWK carbs. If you want to drag race more than dune, 35 or 39mm carbs, Shearer pipes. Shearers usually make the most power, but in a narrower range than CPIs.... 35's will give you a little better throttle response, but 39's will give you a hair more on top end. So...pick/match the combo you want. Quote
crewchief3285 Posted November 15, 2006 Author Report Posted November 15, 2006 well as far as timing 7deg. comp 150 psi, all i do with the shee is some trails normal crusing but strictly drag, no dunes in this area. now the only problem is getting it to hook. im looking for some flat trackers 20/11/9 any brand let me know if you know some one. thanks for all your help. Quote
dajogejr Posted November 15, 2006 Report Posted November 15, 2006 Once you go cub, you'll need paddles for sand, or slicks for pavement. Good luck getting a set of knobbies to hook. Kenda Klaws with ever other row removed might be ok. My holeshot XCRs which hooked like a mofo in grass with my stock motor just fry in everything, grass, dirt, pavement, you name it. I put 'em on the bike to transport it if I'm not going to the dunes, that's about it.... Quote
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