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JD your thoughts on the WB carbon Pro jetting?

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SO I get this sexy new Carbon pro and put it on my bike (2005 CRF450). It comes with a WB "Powerfilter" air filter and a 158 MJ. Instructions say to drop the clip 2 positions(raising the needle) and install the 158 (stock MJ is a 168). This tells me that they are saying the carbon pro will be RICH on the MJ and lean in the midrange-right? I have several friends with 04 250 & 450's that said that jetting won't work at all and to run stock jetting. So I did. I ran it for 20 minutes hard moto and checked the plug. WAAYYYY LEAN.....white with aluminum specs. I see a pro at the track with one and we talk. He says drop the clip 1 position and that he is running a 162- saying your rarely on the main jet (full throttle). I drop the clip one and leave the 168 main in. Ride some more. Still WAAAYYY lean. Drop the clip again- and rode the rest of the day. I did not check the plug yet but now the mid to full throttle pulls noticably harder. I pulled a holeshot ( I have video proof!) so friggin Huge against a gate full of intermediates and experts it was like they were all on 50's. I am anxious to see what the plug looks like. But as lean as it has been, I cant see dropping the MJ all the way to 158. Anyone have any thoughts????????????

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Are you now using clip position #5 counted from the top?

Try turning the fuel screw outwards or run a #45 pilot jet if the bike is lean. I would not lower the main jet more than 2 steps from stock near sea level.

James

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The clip is two positions lower thatn the stock setting ( I believe that there is only one more notch below it but I can't be sure-I do know it is two down from stock for sure) I still havent checked the plug since riding it in this position, but as I said, it ran noticably better at this setting. I am still using the stock 168 MJ. What on earth is WB thinking reccomending a 158-10 steps leaner than stock

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I too have a 2005 450 and just got a WB Alum Pro with the same instructions to change to the supplied 158 main and 6th position. It didn't make sense to me either, so I came here and saw your post. Like to hear further tech help. Thanks! Mike Okano

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Just received the 05 carbon pro for my 2005 crf 450 and read the instructions and it says for sea level that they recommend the stock jetting.

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