by KevinM » Tue Mar 06, 2007 7:04 am
Tmoney... I'm not sure which main jet was stock in the 2005 250R. I though it was a 170. My '07 had a 175 main jet as stock. I went up to a 180 and it seems to run ok in the chilly NJ weather. But the jury is still out on that. I may go back to 175. My bike is 100% stock aside from the jetting. Oh yeah.. I was running the JD blue needle but changed to the Red needle since it's getting warmer. 5th position down. And I just changed the pilot from the 42 stock to a 45. It was still tough to start in the cold with the 42.
I just wouldn't expect stock jetting to be too rich. But I admittedly have less experience than most with jetting.
a 155 just seems too lean to me at 200' MSL. I think the Honda needle of choice is the NCVS. Probable 4th or 5th position for your altitude is where I'd start.
one more thing. If you start changing things around.. make sure you know where you started.. main, pilot, needle, clip, Fuel screw turns.. so you can get back to stock if you aren't getting good results.
And you can always buy the JD kit with a new pilot and follow JD's instructions. Thats been a safe bet for anyone that I know of who's done it.
09 CRF 450R
07 CRF 250R
45 plt /175 main /JD Red-5th pos
FS 2 trns
05 CRF 250X
42 Plt /162 Main /JD Red Needle- 5th pos
CRFsOnly Fuel Screw 1-7/8 trns out (2 turns winter)
TwinAir PowerFlo Kit /Opened Airbox /White Bros E2