by Kiwi » Wed Oct 07, 2009 5:16 pm
~,
The bone-stock 2007 CRF150F that I just bought ran kinda cruddy and would often conk out at idle ... thus, I took the jetting advice from the CRFs Only website. With the new pilot and main jet, the CRF150F ran waaaaaaay better at sea level. However, when I recently took it to Hungry Valley it was very sputtery and weak in the lower revs ... only cleaning up at high rpm.
Thus,
1. I think that I need to adjust the idle air bleed screw ... right? I was told that on carbs that have the bleed screw before the slide (on the airbox side of the carb) that opening the screw adjusts the air volume ... it leans things out; however, carbs that have the bleed screw after the slide (on the cylinder head side of the carb) that opening the screw adjust the fuel volume ... it richens things.
Is this true?
2. Should I drop the needle one step?
3. Is there a non-stock factory Honda needle that you would suggest
2007 CRF450X with modified airbox, Uni filter w/no backfire screen, NCVS needle on 4th, 172 main, CRFs fuel screw at 2, Boyesen QS3, stock smog, 450R cam, FMF Megabomb header, Pro Circuit T-4 muffler, Pro Taper Evo bars, AS suspension