Topic: "Asphalt Dyno" results for SAMCR750

[scondon]

     Sam, your a Wizard!(sorry, Genius was taken haha).  After reading Harry's post in the FAQ section I took your advice and did a WOT plug chop on a loooong uphill road nearby. I have never seen a cleaner WHITER plug come out of an engine before. Everytime i've pulled a plug out of this engine it has been dark and sooty. After adding that baffle a little tan began to appear in that dark soot. I thought it only stood to reason that I should be going down in jet size.

  So the lightbulb in my head is slowly beginning to brighten concerning how to tune these carbs. Takes a little while of you guys bombarding me with all the right technical info before I can begin to merge that info with what I'm looking at/experiencing and gain what can only be "comprehension"

  So what I've got, Sam, is a set of carbs that are too lean at idle (popping on decelleration), too rich in the midrange(I cut the engine before slowing into my driveway and that white plug was black and sooty again), and way lean at WOT. It's a good thing I held on to those 130 mains.

  My question at this point is, should I put larger main jets in now or wait until i've adjusted the needle clip position? I don't want the mid-range getting ANY richer than it already is.

[MRieck]

Good point Sean. I'd go up on the main 2 sizes if it is that white and drop the needle 2 notches. Start there. You need to jump your idle jet up 1 size. I just posted on the other thread how the main has a very direct affect on the needle setting. In fact all fuel circuits overlap and affect the other. Carbs are an organic mixing device. Internal combustion is similiar in that you can't look at it as a series of seperate events...it is a dynamic process.

[scondon]

 Thanks for that Mike. I have no idea where the clips are positioned now as the bike they came off of had been thoroughly modified from stock before I got it. I'm sure that they'll end up at, or near, where you advised me to put them long ago.

   Lesson: working "around" a problem just means ya get to bump into it again and again.

[Sam Green Racing]

Well! , what was the outcome ??

Regards the Genius

Or I am not playing anymore.

[scondon]

   Planning on doing the carb work on Saturday, Sam. This will be my first time messing with the needle clips, I expect it may take a while. I'll keep ya posted.