Carb Q's

[RichM1983]

Hey guys. I was having trouble with my carb running way to rich. My plug was black as coal and soaked with burnt oil. The jet I was running turned out to be a 160. Well I tore the carb apart to put in some new jets and check the needle position. When I was inspecting the needle and slide the slide has a star symbol and a 60 by the whole the needle comes out of. Is that stock? Also once I took the needle out I noticed it had NR 14.6 9 on it. Is that the stock needle? I ask all of these questions because when I got the carb it had a huge jet like a 170 something in it and I suppose it was used on a big bore motor which is why I wonder if these other components are stock or way bigger than my stock motor needs. All I have is a foam filter, no airbox lid and a full LRD exhaust with stock reed cage and fiber reeds. Also the clip was in the fourth position and I moved it to the the third position. Is that leaning it out or making it richer? Thanks for the help. Later.

[Aceman]

I'm still learning but I'll tell you what I do know.

The slide is a #6.0 which is right in the middle of the slide range. Should be fine.

Your needle type??? I have no idea. I just bought a 39 pwk and had the same problem. I removed the needle, looks like it's aluminum and it's stamped N O Z E.:huh I'll end up replacing it with a factory keihin needle probably a dgh or cel just because I've never heard of it and I'm scared to run it.

Since you moved the needle position up, you leaned it out some, most carbs are ran with the clip in the middle position, I'd run it and see how it does. If the midrange is still rich, move the clip up one more time. It's summer time, time to lean the jetting up a little. This is all assuming your motor is not burning tranny oil and fouling your plugs.

Your 160 main doesn't sound to large, I run a 165-168 with 36 pj on my 310. I can't tell you the stock 250r jetting right now, I don't have my manual in front of me.

More info about slides, needles at www.keihin-us.com
Jetting info www.duncanracing.com

[RichM1983]

Thanks for the reply. I shouldnt be sucking tranny fluid because I just put brand new crank seals and bearings in. Ill try out the new jets tomorrow since its going to be nice out.