imlostagain Posted October 15, 2005 OK , I'm sure some of you knew I'd be back with more questions .... I got a chance to put everything back together and go for some test riding and here are the issues . There is a serious bog if I nail it from idle but if the rpms are up at all this is not an issue just off idle. more noticable on the stand . Bike pulls very well if I ride aggresively but is a bit sluggish if I am coasting and try to accelerate at roughly mid throttle . 50 % of the time the engine takes a good 10 seconds or more to idle down . Current setup: stock motor /exhaust 3x3 '98 yz400 fcr carb JD blue needle 3rd clip 160 main 38 pilot PAS 5/8 turn fuel mix screw 1 1/2 turn Thanks again.. Share this post Link to post Share on other sites
Wayward Son Posted October 15, 2005 open the fuel screw to 2 turns. Share this post Link to post Share on other sites
imlostagain Posted October 17, 2005 Alright , I've turned the screw 2 turns out and it feels a little snappier but I still get a serious bog just off idle to the point the bike will die if I don't back out . I can however give a second twist of throttle immediatly following the bog and the bikes sounds awesome .The bike will run very well if I really push it but it seems a little lazy if I try to transition from about mid throttle to full. Any thoughts? Share this post Link to post Share on other sites
imlostagain Posted October 17, 2005 Forgot to mention that the exhaust simply smells rich . I ran it just long enough to adjust the mcct in the garage and it just stunk the place up FAST . Share this post Link to post Share on other sites
Baron Von Beard Posted October 17, 2005 Move your clip down on the needle and see if it helps. It sounds like it may be too lean on the transition. Make sure that you idle is set right. Too high and you'll get the hanging idle. Share this post Link to post Share on other sites
imlostagain Posted October 17, 2005 I did end up adjusting the idle and it has settled down as you stated. If I drop the clip down on the needle that will have an affect on primarily the sluggish transition at mid throttle ?? or will that also help the off idle bog ? Share this post Link to post Share on other sites
Baron Von Beard Posted October 17, 2005 It should mainly clean up the mid-full transition, but can help with off idle also. Have you messed with the pilot jet at all? One other thing: If you move the clip up on the needle, the needle will block the main jet longer and lean out the transition to WOT. Conversely, if you move the clip down on the needle, it will allow the main jet to open up sooner in relation the throttle position. The clip position just changes when the main jet becomes fully unblocked in relation to throttle position. If it smells rich or puffs some black smoke when you crank the throttle, move the clip up on the needle to slow down the transition to WOT, and it might cure what ails you. Share this post Link to post Share on other sites
Wayward Son Posted October 17, 2005 you are testing throttle response while riding correct?fully warm? Share this post Link to post Share on other sites
imlostagain Posted October 17, 2005 Yes , the mid to full throttle response was riding on the streets with warmed up motor . The major bog off idle I refer to is far more noticable on the stand ... I don't recall it being so bad on the street in part because I generally rolled the throttle from a stop and gave it a chance to get the rpms up a little before I got on it. Share this post Link to post Share on other sites
Baron Von Beard Posted October 18, 2005 Don't test on the stand. It's dang neart impossible to cure the bog when the bike's in neutral. Share this post Link to post Share on other sites
Wayward Son Posted October 18, 2005 try the red needle 4th clip. Share this post Link to post Share on other sites
Baron Von Beard Posted October 18, 2005 try the red needle 4th clip. How more specific could burned get. Dang he's good! Share this post Link to post Share on other sites
imlostagain Posted October 18, 2005 Unfortunately , I will not be able to adjust it for a day or so but I will try the needle/ clip position and will update with the results.. Share this post Link to post Share on other sites
