Pete in PA Posted November 1, 2006 Share Posted November 1, 2006 I recently went to 1 step bigger pilots, took the mains up so they all match and shimmed my needles. My question... Which circuit covers cruise on the highway in top gear, throttle barely cracked. THe bike runs great but now I'm down 4-6 mpg. and want it back. Should I turn the pilot screws in to 1 turn out from the 2.5 turns out they are now? Or am I mostly on the slide needles at that point? Thanks! Quote Link to comment Share on other sites More sharing options...
bartonmd Posted November 1, 2006 Share Posted November 1, 2006 I recently went to 1 step bigger pilots, took the mains up so they all match and shimmed my needles. My question... Which circuit covers cruise on the highway in top gear, throttle barely cracked. THe bike runs great but now I'm down 4-6 mpg. and want it back. Should I turn the pilot screws in to 1 turn out from the 2.5 turns out they are now? Or am I mostly on the slide needles at that point? Thanks! At the highway cruise point, you're above the idle circuit's main effect, and below the needle's main effect... You're right smack-dab in the middle of the actual pilot jet size's effective range... This is the reason I left mine with the stock size pilot jets and 3.5 turns out... because I didn't want to lose the mpg on the highway, because that's primarily what I do, and changing from punched pipes to slip-ons made any wierdness in that range go away... Mike Quote Link to comment Share on other sites More sharing options...
tomek Posted November 2, 2006 Share Posted November 2, 2006 What is a cruise ? 120 ? Well if it is 60-80 pilot circuit is a main source of fueling,I mean they are overlapping somewhat . Go back to your "old "pilots and play with the screw or do just a screw. Always select main jet first and play with the rest later .Actually this is better-,will answer all your questions http://www.factorypro.com/tech/carbtun.html Quote Link to comment Share on other sites More sharing options...
Pete in PA Posted November 2, 2006 Author Share Posted November 2, 2006 Hmmm......OK another question. Does the pilot screw control the fuel through whatever pilot jet you put in or are they 2 circuits working together? In other words If I turn the screw closed will it stop all fuel through the pilot jet? I have and copied the Factory CV instructions. but they don't explain this. Quote Link to comment Share on other sites More sharing options...
bartonmd Posted November 2, 2006 Share Posted November 2, 2006 Hmmm......OK another question. Does the pilot screw control the fuel through whatever pilot jet you put in or are they 2 circuits working together? In other words If I turn the screw closed will it stop all fuel through the pilot screw? I have and copied the Factory CV instructions. but they don't explain this. Yes, it controls the fuel through the pilot jet at idle only, from what I gather... It's much like the needle and the main jet... The needle controls the fuel from the main jet, until the needle is all the way out, and the main jet it the main controller... It's like that, only on a smaller scale... Mike Quote Link to comment Share on other sites More sharing options...
tomek Posted November 3, 2006 Share Posted November 3, 2006 It has been a while since I played with carbs btu as far as idle system this is how it works. There are tiny holes at bottom of throttle bore that come progressively into play when throttle begins to open.I understand that they are all controlled by pilot circut( fuel+air emulsion flow thru them) but the first one is controlled by screw also. Let`s say you found correct screw position for given pilot jet ( max idle rpm test) but bike hesitates when you crack throttle slightly.In this case proper way to do it is to change to bigger pilot jet,readjust the screw for the best idle and test again. If you turn the screw all the way in bike will not idle. Anyway,I`m only experienced with Mikuni carbs,Honda uses Keihin,I`m not sure pilot circut works the same way. Quote Link to comment Share on other sites More sharing options...
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