AKheathen Posted June 18, 2009 Report Posted June 18, 2009 OK, here's the deal, just put my pcp's on and I'm jetting in a confined space (back yard woods) can't get a plug chop 'till i get where I'm going. my main question is- are they generally really thirsty pipes. stock port, near sea level, 70 degrees, boysen power reeds(the clear ones) fmf silencers(don't have the pro-circuit stingers) so far, I'm up to 340 main, 25 pilot, longer,leaner needle, 2nd clip from blunt end. i can get it tuned in from idle to over half any rpm, but the problem is, wot and near sounds like a lean bog @ low rpm. if i just barely touch the throttle a second first, it'll take the wot stab and walk just fine, but i don't want it to do it in the woods, and just looking for extra opinions. can't get 27.5's in time, and the fmf's wanted 290's in the same conditions. have tried stock needles, too. before you ask- good blue spark R/L, pickup gap set. carbs all good/cleaned, everything where it should be, slides/choke tube/synced, etc. no air leaks, reeds good, this is getting time consuming, and i have allot to do. the fuel is a few weeks old, stored in a sealed can in the shade. kinda what I'm thinking :shrug: :shrug: :shrug: :shrug: :shrug: :shrug: :shrug: :shrug: :shrug: Quote
278 Posted June 18, 2009 Report Posted June 18, 2009 the idle to half throttle will be your pilot jets and your clip, but your mains are way high man, Im at like the same sea level over here on the east side of town but i have... Toomey T-5's, aggressive trail port, wiseco prolites, 20cc dome cool head, +4 timing, eliminated air box lid, welded crank, and ported reeds with dual stage petals and I was using 330's in my carbs to do my heat cycles when it was 50 degrees out I think I was a little lean and should have gone to 340's but with all the other mods and 20 degrees cooler, I would think it's something else. Quote
01banch Posted June 18, 2009 Report Posted June 18, 2009 (edited) Well I do not think he is too rich nessascarily I run 420's in a stock stroke dune ported bike with PT mids on it. The plugs and how your motor is running will tell you how rich or lean you are. Even in the same town all my buddies bikes set up similar to mine are all jetted differently. Edited June 18, 2009 by 01banch Quote
Snopczynski Posted June 18, 2009 Report Posted June 18, 2009 Airbox, pod filters? What octane fuel? Quote
AKheathen Posted June 18, 2009 Author Report Posted June 18, 2009 i started @ 290. swaped needles a couple times. no lid, 20cc's, and t-5's are realitively smaller on the head and dump sections than the pc's, which effects jetting. i'm just hoping someone can short-cut me closer to save time. it takes time letting it cool to change the jets and warm it back up to operating temp. i'm at the point in my life that burns start to get annoying. :biggrin: i'm gonna play with the needles some more, and then bump top 350 and try to make it sputter. Quote
AKheathen Posted June 18, 2009 Author Report Posted June 18, 2009 Airbox, pod filters? What octane fuel? i can only get 90 @ the pump, but i'm gonna search out something higher to mix in town. i know i can at least get some LL avgas Quote
AKheathen Posted June 18, 2009 Author Report Posted June 18, 2009 ok, not nuts. she wants more fuel. i moved the needle 1 clip leaner, and it still bogged under load/off idle, so i made another lap, and when it bogged out, i let it keep goin till stall, and rolled back down out of the woods. pulled the plugs, and no fuel, just a little oil on the base. moved the needle all the way rich, added a quart of regular gas to the mix, warmmed it up for a couple min, and made a couple more laps. the bog/hesitation is almost gone, and it sounds a little zinggy on top, so i'm letting it cool to bump the mains. this backwards jetting method is a pita! Quote
Snopczynski Posted June 18, 2009 Report Posted June 18, 2009 Your better of just saving your time and jetting it by feel, then to keep pulling the plugs. Any variations in rpm or throttle opening can cause the plug to be hard to read. I usually only do wot plug checks after running the bike 5 seconds or more wot. Quote
AKheathen Posted June 18, 2009 Author Report Posted June 18, 2009 i pulled the plug because i wanted to see how much fuel/oil was on it when it bogged out and stalled. was wondering if i was mistaken about the lean bog. do your pipes like alot of fuel? i'm just perplexed that it wants at least5-6 sizes more than the fmf's, and keep second-guessing myself. thanx Quote
Overboost Posted June 20, 2009 Report Posted June 20, 2009 I have the pro circuits and 304 silencers, I run the mods listed in my sig and a 320main, I go by feel and sound, not so much plug. I have had my head off with the plugs looking white when I check them, and the pistons look good. no lean spots, nice oily walls. my bike pulls hard all through the range and does not hesitate except on the initial slam of the throttle from a slow roll or idle, but that a 2 stroke. otherwise, my bike runs really good and my plugs look lean as shit. slight ghost ring when cut and no color whatsoever, I run 115 race fuel turbo blue and ams oil dominator. Quote
AKheathen Posted June 23, 2009 Author Report Posted June 23, 2009 I have the pro circuits and 304 silencers, I run the mods listed in my sig and a 320main, I go by feel and sound, not so much plug. I have had my head off with the plugs looking white when I check them, and the pistons look good. no lean spots, nice oily walls. my bike pulls hard all through the range and does not hesitate except on the initial slam of the throttle from a slow roll or idle, but that a 2 stroke. otherwise, my bike runs really good and my plugs look lean as shit. slight ghost ring when cut and no color whatsoever, I run 115 race fuel turbo blue and ams oil dominator. yah, i just got back from jetting hell. finally got down to the beach where the humidity would make drastic changes by the hour, but i could really rip around and feel the jetting. i was forced to run bel-ray after going rounds with the dealership, which claimed that they never carry the oil that i've been buying from only them for a year, then claiming it was a fluke, then they only ordered it so people can run it in their diesels, etc.. but i got in a chop with a little lean @330 (less than 2mm around chocolate) then sputtery 4 hrs later. then zingy the next day ridding up to the gas station, and back to sputtering across the beach less than an hour later. I NEED DIAL-A-JET!!!!! like i said, i just pulled the plug to see if i was wrong about the lean bog, and chocked it up to the fmf silencers not having enough backpressure. when she rips, she really rips, though. so, you say there is still a hesitation with the right silencers? what kind of portwork did you do? Quote
Overboost Posted June 23, 2009 Report Posted June 23, 2009 I dont have any port work yet, that is a project for this winter. only mods are in my sig. my bike feels great, no hesitation, no bogs and feels great compared to when I first got it bone stock. friends bikes that were stomping my ass are now counting tail lights from 3-5 lengths back. in the trails, dunes, hills, anywhere... Quote
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