Cheers !! I will keep you posted. [img]i/expressions/face-icon-small-smile.gif[/img]

 

OK guys. I started my bike and let it idle for about 5 mins. I didn't see any glowing in the headpipe but I when I blipped the throttle there is a bit of a stumble and when I blip it 3 times in a row it stalls. Is this a sign of being too rich. Also last weekend I noticed that the bike did run fine through the throttle but only after it was really warmed up. If I rode it hard say for only letting it warm up for 3 mins or so there was a bit of a stumble then it went away after a few passes up the road.Suspicions are that my pilots are rich. I think I am gonna go with 25 pilots. My air fuel is at 3 1/8 turns out L and 3 3/8 turns out R. What should I set them to with the 25's. Rich out, lean in right. I was thinking 3 turns out left and 3 1/4 turns out right or 2 3/4 L and 3 R.

Thanks

 

Yes, go to the 25's for your Pilot Circuit.

Actually, turning your "AIR" - Fuel screw OUT will lean out your mixture because you are introducing more air into the mixture.

Do one thing at a time to dial it in, if you change too many things all at once you won't know what was causing you the problems.

 

Greg the raptor carbs. let more fuel in by turning the "fuel enrichment" screws out. Most 2 strokes and older bikes work the way you said and were called "air screws"

 

Hmmmmmm. I spent quite a bit of time talking to a the Service Tech. last week on carb tuning for our new Scrambler 400 (2-Stroke) and he was telling me about the "air screws". I told him that I had thought it was the other way around, but he said "no, they are air screws, so turning them out adds more air and will lean out the mixture. He was talking about Makuni carbs in general as if they were all the same. Oops.

I didn't tell him that I was baseing my thinking from my Yamaha Raptor [img]i/expressions/face-icon-small-blush.gif[/img].

Thanks for the the clearification sixsixT.

 

Is there a reason why I can't turn my mixture screws? I just started a little rich yesterday all of a sudden. Anyway If I punch it from idle it hada little blip, a pain when I'm trying to do wheelies. It had 25 pilots, 165 in L and 160 in R. I tried to change my mixture screw but it wont turn at all, and I don't want to strip it, any ideas? Any help is appreciated,

Patrick

 

Your last post said you had a 165L and 160R. If you are sitting on the bike the carb to your left should have the 160 and the right should have the 165. This could be part of the jetting not acting correctly. Just trying to help' SLIM.

 

Yes, the fuel mixture screws turn out (counterclockwise) for a richer mixture. I run 27.5 pilots with no problems. Get a proper tool too adjust the idle circuit while the engine is running.......you are looking for the settings the give the smoothest, highest RPM's. Ideally, you want too use a vacuum guage too adjust your idle circuit.

 

After looking at your plug, I would up the mains too 165-170 too.....the Raptor makes more power in a rich condition (this is not gonna cure your idling, loading up problem though).

 

I had the same problem with my Raptor stalling when blipping the throttle when idling. I tried everything also then I read an old article in one of the atv magazines stating a similar problem. They suggested raising the idle slightly. I did that and my problem went away.