highroller355 Posted September 23, 2008 Report Posted September 23, 2008 1 st im at sea level motor 421, 4 mil long rod cub, cool head with cc domes, billet one piece intakes, v force 3 reeds , 39 pwks with billet bowls and pods, in frame shearer pipes , and +4 on timing runs on 112 to 114 octane. what should my jetting and timing be at? i mostly run quarter and asphault thanks in advance . Quote
rubberneck Posted September 23, 2008 Report Posted September 23, 2008 Highroller, i have the exact same set up. You didn't mention which needles are in your 39s, so i will tell you my set up. I had 58 pilots, DGH needles in the middle and 185mains. It is a bit fat on bottom, could probably go to 55s. Starts without choke when cold, and had a stumble right off the bottom, but idles great and does not load up plugs, so must not be too far off. Top is actually on the edge, plugs look a little light when doing a plug chop. You are going to hear 50 guys get on after me and tell me the mains are way too huge, but i can post pics of the plugs. It must have to do with the needles im not sure. A lot of guys run CELs and maybe thats why they all run 155-160 mains. Just go fat and work your way down carefully (ask me how I know LOL) I run +4 timing because i dune mine for extended periods. Everybody says cubs love timing. Jeff told me to run+7 if I was dragging only, but I dont know for 1/4 mile. That is longer than i would see in the sand. Quote
dajogejr Posted September 23, 2008 Report Posted September 23, 2008 Just goes to show you....every motor is different. In my 4 mil cub, Shearer inframes, cleaned up on 110 octane I ran 48 or 50 pilots, CEL needle and 152 mains...and it was crisp, 35PWKs.... We only use 55 pilots in 39PWKs for alky bikes here.... Definately start rich...work leaner from there. Quote
rubberneck Posted September 24, 2008 Report Posted September 24, 2008 Just goes to show you....every motor is different.In my 4 mil cub, Shearer inframes, cleaned up on 110 octane I ran 48 or 50 pilots, CEL needle and 152 mains...and it was crisp, 35PWKs.... We only use 55 pilots in 39PWKs for alky bikes here.... Definately start rich...work leaner from there. Yeah, I know it. Jeff set them up for me with 180s and 60pilots, and I asked him why it was so different than what I always see recomended on here. He said its the 39's compared to 35's I think a lot must have to do with the needle. I dont know. I just know that high compression teamed with a main jet that was probably a size or 2 small and some long high speed runs cost me a piston. Heard it break up once, got out of it, and it was too late. oh well, going to have jeff drag port it and put in the override like i should have the first time. good excuse to upgrade right. LOL Quote
Hilarious Posted September 24, 2008 Report Posted September 24, 2008 (edited) i am wanting to say that i have 178 mains, CEL needle on middle groove, 60 pilots and +7 on the timing w/ drag port right around sea level. this is on a new engine so i have not started leaning it out any. i do know it is a bit fat on the low end. starts up w/ no choke. runs like a mad man on top and isnt breaking up. Edited September 24, 2008 by Hilarious Quote
dajogejr Posted September 24, 2008 Report Posted September 24, 2008 I would bet where you ride there are no mosquitoes for miles...LOL. Honestly, there are two ways to do this... The builders are going to start you out PIG FAT so you don't smoke a motor. Very, very smart practice. Lean down from there...and you gotta have a place to ride to do that. Or you could go to a dyno and use the A/F meter to get you dialed in, keeping in mind that your actual riding locale might differ a bit from a controlled area like a dyno, but at least you KNOW your close if not dead on. Some people are intimidated by carbs....some people, like Hilarious, are intimidated by a small meal. LOL... Pick your poison.... From my personal experience with similar builds, those jetting numbers are WAY rich... Quote
STINKYDELUXE Posted September 24, 2008 Report Posted September 24, 2008 (edited) "Or you could go to a dyno and use the A/F meter to get you dialed in, keeping in mind that your actual riding locale might differ a bit from a controlled area like a dyno, but at least you KNOW your close if not dead on." dajogejr where in MI would you go to do this? just wondering Edited September 24, 2008 by STINKYDELUXE Quote
dajogejr Posted September 24, 2008 Report Posted September 24, 2008 "Or you could go to a dyno and use the A/F meter to get you dialed in, keeping in mind that your actual riding locale might differ a bit from a controlled area like a dyno, but at least you KNOW your close if not dead on." dajogejr where in MI would you go to do this? just wondering Lakes motorsports in Waterford Michigan. If you don't have a LONG swingarm (up to 4 over) RB Porting near Lansing MI. Dan Hull & A&S near Lansing RDZ Racing in Fowlerville... That's to name a few. I'm pretty sure Dan @ A&S is a motor dyno, so...you'd have to take the motor out of the bike to run it. It is not a chassis dyno. Perhaps someone can chime in on that. Quote
wesw Posted September 25, 2008 Report Posted September 25, 2008 45 48 pilots, middle with dgh and 160 mains 165 if it was cold out. what i used to run. with 39s pwk Quote
highroller355 Posted September 25, 2008 Author Report Posted September 25, 2008 also have 205 compression , here is my set up on carbs way to fat down stairs stock needle middle clip, 60 pilots, 178 mains thinking of going. 58-55 pilot with 182-185 mains and timing still at +4. heard the timing should be +4 for 1/4 mile Quote
dajogejr Posted September 25, 2008 Report Posted September 25, 2008 205 PSI??? WOW....that thing is going to come out of the hole like a sunnuvabitch, but I have a feeling it will fight itself on the big end...wow. Quote
highroller355 Posted September 25, 2008 Author Report Posted September 25, 2008 205 PSI??? WOW....that thing is going to come out of the hole like a sunnuvabitch, but I have a feeling it will fight itself on the big end...wow. full weight bike with 250 pound rider, the extra compression is going to be needed to get up and go :biggrin: :biggrin: :biggrin: :biggrin: Quote
dajogejr Posted September 25, 2008 Report Posted September 25, 2008 By no means am I telling you how to setup your bike...my personal preference is less compression and more timing. Again...I ride 300 foot sand, different than you...and on alky. With a lighter bike but fat kid at the helm still....LOL. Quote
highroller355 Posted September 25, 2008 Author Report Posted September 25, 2008 By no means am I telling you how to setup your bike...my personal preference is less compression and more timing. Again...I ride 300 foot sand, different than you...and on alky. With a lighter bike but fat kid at the helm still....LOL. i appreciate the help, i was told i would need the comp to get my fat ass going the smaller comp wouldn't work as good. i will be calling fast for another set of domes and bump timing and ill let you know the diffrence. what do you think comp should be around. thanks again to everyone for help and input. Quote
Hilarious Posted September 25, 2008 Report Posted September 25, 2008 i appreciate the help, i was told i would need the comp to get my fat ass going the smaller comp wouldn't work as good. i will be calling fast for another set of domes and bump timing and ill let you know the diffrence. what do you think comp should be around. thanks again to everyone for help and input. i am guessing 180ish? i need to check mine to see what it is. Quote
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