tbd Posted April 27, 2007 Report Share Posted April 27, 2007 i need some input on settings for my banshee. i have, passion hot mx 12 port noss cool head with pump gas domes t-5s v-force reeds dyna ignition 33pwks pro-flo with k&n and no lid i know my main is at 165, my pilot a 48, and my needle is at the third clip. i'm not sure what the needle is, its what ever comes with the carb. my problem is the transition from 5th to 6th i have a lag at the begining and then it picks up, not a bad lag more like a lose in momentum. i was thinking i need to change my needle? Quote Link to comment Share on other sites More sharing options...
Toomey Banshee Posted April 27, 2007 Report Share Posted April 27, 2007 Get rid of the box and go with pods. Jet up acordingly. Start at 170's and work your way down. Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted April 27, 2007 Report Share Posted April 27, 2007 i need some input on settings for my banshee. i have, passion hot mx 12 port noss cool head with pump gas domes t-5s v-force reeds dyna ignition 33pwks pro-flo with k&n and no lid i know my main is at 165, my pilot a 48, and my needle is at the third clip. i'm not sure what the needle is, its what ever comes with the carb. my problem is the transition from 5th to 6th i have a lag at the begining and then it picks up, not a bad lag more like a lose in momentum. i was thinking i need to change my needle? If your in 5 and 6 gear I would say your probably at WOT witch is the main jet. For being stock cylinder and stock stroke the main is pretty big. Most people run in between 152 and 158. I think the CGL needle comes with the 33's. A common needle to swap out to is the CEL. Same diameter and Taper just a little shorter in Lenght. If drop your needle clip postion and eventually run out of adjustment. Go to the CEL in the middle and clip and start over with adjusting the needle clip postion. Your pilot jet seems right on. Most people run a 48. Patriot Racing recomend that I start my jetting out at (165 main, CEL middle clip, 48 pilot) for my 400cc Drag Ported 4mill stock cylinders, and work my way down. That will give you kind of an Idea that 165 main is plenty big for a mx ported stock stroke cylinder. Quote Link to comment Share on other sites More sharing options...
tbd Posted April 28, 2007 Author Report Share Posted April 28, 2007 thanx for the replies, i'm going to get some needles and do some testing. i'm really worried about the main being close because this now my 3rd set of pistons i've done, due to bad jetting recommmendations from jim. Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted April 28, 2007 Report Share Posted April 28, 2007 pm "wesw" here on the site. hes prolly got more experience jetting these motors than anyone.. Quote Link to comment Share on other sites More sharing options...
wesw Posted April 28, 2007 Report Share Posted April 28, 2007 thanx for the replies, i'm going to get some needles and do some testing. i'm really worried about the main being close because this now my 3rd set of pistons i've done, due to bad jetting recommmendations from jim. what did jim recommend if yo udont mind me asking.?????????? also how much timing you running, i see your running a dyna also, whats your compression psi?? give me some info ill help you with the jetting. but first would like to understand why your going thru pistons. Quote Link to comment Share on other sites More sharing options...
jayzx10r Posted April 28, 2007 Report Share Posted April 28, 2007 My jetting isn't perfect yet...at least the needle selection...the mid is still fat. I'm running a 152 main, 48 pilot, 2 turns out on the air screw, 48 CGL needle in the middle (the one that came with the carbs). I'm gonna drop the needle 1 next time out because there could be a better transition from mid to top at 3/4 throttle. http://www.keihin-us.com/am/products/pwk.php That is a link to the Keihin PWK spec and tuning guides that can assist you in fine tuning based on throttle position. Start with the main and work backwards. Main to needle to pilot to air screw. Did you install the pilot jets? If not, stock is a 52. I run 50/50 100LL av-gas to premium pump fuel and have 160 lbs comp on a 4mm stroker with the same carbs near sea level. I don't have experience with the air box but it is my understaning that it will be a bit richer. That being said, I'm wondering why you are on your 3rd set of pistons.... Is it one that seizes or both? Do they look like they have been run hot without oil? Is there signs of detonation? Do you have a fuel flow problem? What oil do you use? Maybe it is time for a leak down test.... Hope this helps... Jay From SanD. Quote Link to comment Share on other sites More sharing options...
wesw Posted April 29, 2007 Report Share Posted April 29, 2007 jay z you cant compare one motor to another stuff is different. also i think its better to go from the pilot to the mains not mains to the pilot. still waiting for tbd to reply. Quote Link to comment Share on other sites More sharing options...
tbd Posted April 29, 2007 Author Report Share Posted April 29, 2007 ok i have around 140 psi with 21cc domes. i haven't even fooled with the ignition yet, so its on stock curve. when i 1st had the porting done i started out with stock carbs and jim gave me jetting recommendations that where the pilot was way rich and the main to small i think it was a 350 main. i broke it in just how he said and started to get on it a little more and didn't run well so i wanted to do a plug check. so i'm in 6th about ready to kill it when it lost power and i killed it right away. come to a stop and i see both spark plugs are loose, i take them out and both of the straps are half way melted off. i knew right away the pistons were done, the rings were welded to the piston. both plugs were the same so it wasn't an air leak. i called jim told him what happened, and couldn't see how 350 main was too lean on stock carbs. so i ordered a new set of pistons and fresh set of copper washer for the noss head. i get the box in the mail with washers and one piston. it wasn't charged on the bill so i got the other piston at the local stealer. now i'm back fresh motor all broken in i went right up to a 380 or 370 main on stock carbs dropped one size on the pilot, and had it pretty good with my plug checks. but i still had that problem with 5th to 6th no matter how i winded it out or what the jetting was i couldn't cure it. i figured i was at the limit of what the stock carbs could do for me. so i purchased a boss intake and 33pwks from jim. his jetting recommendations were 160 main, 55 pilot, needle middle clip. the carb came with a 165 main i think, and i told jim it was about 20-30 here where i'm riding and he said 160 main should be plenty big enough. i ran the 160 for a little bit and it didn't run well so i upped it to a 162. went out on the lake and it ran good. that week i posted my specs up on this site (back in feburary) and banchetta said i should be running a 170 main. it was too late cause my compression was fubar'd. the ring lands were screwed up on one piston so i replaced both to be safe. this past week i put her all back together and i'm in the process of breaking it in, i figure now that its warmer a 165 should be ok to start. i'm not trying to bash jim, i'm just wondering if i have the wrong port and don't know it. and yes the 33pwks did help out a lot but i still am not happy with the initial 6th gear lag, hell with this set up it shouldn't be a problem with stock gearing right? sorry for the long post i just wanted to try to explain my 2 year situtation the best i could Quote Link to comment Share on other sites More sharing options...
wesw Posted April 29, 2007 Report Share Posted April 29, 2007 (edited) i think your running timing to advance cause your going thru plugs the strap is getting eating off, and your rattling plugs loose which is a sign of knock what gas are you running. 91`octane or better i would say try to get some 100LL from an air port. what color are the plugs when they rattled loose, gray poofy?? or white. if you running an adjustable plate put it at zero and leave the dyna on stock that will be still 2-3 advance. as for jetting i would say 55 pilots, needle 5th clip and 150 mains. then adjust from there. the bike will like lot of fuel in the mid. and the reason your not pulling 6th gear is im guessing your lean in the mid and it has a lot of lag trying to get fuel till the main puts enough there to make it pull. i ran a 145 main on my old pj 4mm so dont be scared of being that low at 1000ft but it like more fuel down low and mid. you will have to see if the bike will idle with 55s, it should like 1-2 turn on the air screws, then you will need to sync the carbs up at idle. jeff sells a good carb sync tool. then you will have to adjust the slide to where they are very close to the same. also if you put new needles in let me know cel, del would work good cel more being its a 350 if its a 4mm i would suggest del, dek. if you have any other question pm me and ill talk stuff thru or give me your phone number and go thru stuff. wes Edited April 29, 2007 by wesw Quote Link to comment Share on other sites More sharing options...
tbd Posted April 30, 2007 Author Report Share Posted April 30, 2007 thanx a bunch for the info, i rod it today (breaking it in) and so far so good. i don't have a 4 mil so i'm going to get a hold of some cel needles, finish breaking her and start tunning. again thanx wesw for the advice Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted April 30, 2007 Report Share Posted April 30, 2007 Like wes said. I would imagen your problems were caused by low octane fuel and detonation. You dont really eat the ground straps off the plugs by being lean. Wes knows his passion race engine jetting. :thumbsup: Quote Link to comment Share on other sites More sharing options...
tbd Posted April 30, 2007 Author Report Share Posted April 30, 2007 i have 21cc domes that should be good for pump gas? and i don't have a timing plate all i have is the dyna with the harness removed, so it will have a stock curve. like wes said though it has 2-3 advance even on the stock curve. i want to be running pump gas cause in upstate ny the gas stops don't have anything over 93 octane Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted May 1, 2007 Report Share Posted May 1, 2007 There isnt any real way to tell with out doing a compression check. I would think with 21 you should be ok on 93 with no timing advance. Quote Link to comment Share on other sites More sharing options...
wesw Posted May 1, 2007 Report Share Posted May 1, 2007 are they pro design domes or something more custom you might check your squish. it could be really tight and causing problems. use some solder adn smash it, between pistons and domes then mic it. Quote Link to comment Share on other sites More sharing options...
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