SyNtAxx Posted April 15, 2004 Report Posted April 15, 2004 Hey all, Well i am expecting weather around 70 degress this weekend here in PA. I was jetted for march at 360/30 and it seemed to run ok for temps around 45-50. I just rode the bike today...temp was about 60 degrees today and it seemed like it was sputtering and carrying on just about all over the throttle range. I would think the mix would get my richer because the weather is getting warmer correct? So i must jet down now correct? I didnt run the bike for about 3 weeks...but i doubt the carbs gummed up that quick? I run Klotz supertechniplate(Castor). I am jetted at 360/30 needles at stock location...should I jet down now? i just dont want to toast my new topend and porting...see sig below for complete mod list. I pulled the choak while I was riding and it seemd to almost shut the engine down...so I imagine i am just running rich the way I am jetted now? Please suggest what I should do..... Thanks a bunch in advance... Nick Quote
sredish Posted April 15, 2004 Report Posted April 15, 2004 Do a plug chop to see how your plugs actually are, and if need be then do a jetting change. Your correct that warmer weather will make it run richer than before, but before you go tearing things apart, check your plugs. Read the Jetting FAQ and see the Plug Chop and How do I know if I'm rich or lean. Quote
SyNtAxx Posted April 16, 2004 Author Report Posted April 16, 2004 Hey, My plugs are charcoal grey.. i guess i will have to put in a new set of plugs and try again Quote
Banchetta Posted April 16, 2004 Report Posted April 16, 2004 Sounds like the needles are too rich. Lower them down to the 2nd clip from the blunt end. I bet it clears up alot.... Quote
SyNtAxx Posted April 16, 2004 Author Report Posted April 16, 2004 Hello, Wow....so you want me to lean out the needle? Leaner than stock? Can yuo explain to me why?.... Please dont mis understand...I am not questioning your advice...just curious how/why you think leaning the needles is the way to go.... I am by no means an engine/jetting master. Thanks again.... Nick Quote
itsaripper Posted April 17, 2004 Report Posted April 17, 2004 You are right about the jetting, it needs to go down some. As the heat in the air goes up the jetting needs to go down. When you move the clip on the needle you are like only going one fifth of a point on a jet. It is for fine tuning the carbs. Most of the time you don't need to mess with the needles when jetting. Anyway try it. Quote
Indubitably Posted April 17, 2004 Report Posted April 17, 2004 Banchettas theory is: The needle is basically for midrange and the Mains you have now are much larger than stock so there is obviously more fuel getting in there so if you drop the needle there will be less fuel to lean it out, but there is still more than stock because of the size of the main jets. Quote
Banchetta Posted April 17, 2004 Report Posted April 17, 2004 Indubitably is right on, also some pipes require less fuel at certain throttle ranges, this where the needles, pilots, and mains come in....You wide open throttle will want more, but the mid-throttle might need to be less....Ex: my mods at the bottom are 300 mains, needle 5th clip, and stock pilots. I just put a stroker motor w/ porting in it, Now my jetting for stock carbs is 380 mains, needle 1st clip and stock pilots......every motor is a little different w/ different combos so you have to fine tune the jetting to YOUR bike...Jetting is an art and can be figured out w/ trial and error...Its a pain in the ass, but the results are well worth it and have great gains from bottom to top.... Quote
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