Originally Posted by Kevin 007
I also mentioned that the sputter was happening between idle and 1/4 throttle. Well its actually between idle and maybe 1/16 throttle! It happens just as I open the throttle the slightest amount.. But as soon as I open it any further it runs GREAT!!! and idles great to
usually a stutter that low (does it go guh/guh/guh then recover instantly and rev fine. like it makes a stutter noise (but not a bog/power loss) when you just ride it with throttle barely cracked open?) is USUALLY a pilot/slide transition issue. or maybe slide/needle transition. what's happening is the slide cutaway is too rich compared to the needle and pilot. the only real way to get rid of it is to go with a leaner slide. that might get rid of the stutter, BUT you may suffer powerwise...(i just went through this on a another bike. replaced slide with leaner cutaway, bike reved and sounded awesome on the stand, but under load it bogged out bad - the bike needed the richer slide to make power in that crucial spot.... i would not recommend changing the slide. you can either lean/richen the pilot out 1 step, or richen/lean the needle 1 step. that may fix it (not sure which way you need to go...) or maybe playing with the airscrew a bit more will get rid of it... the problem with any of these fixes is it may affect how it idles, and ultimately how easy it is to start.......
you really should pick a premix mixture and stick with it. fix jetting with brass, not liquid...