Too lean???

I have been talking with Mr. Dean and he has given me a few suggestions, but my bike keeps rejecting them. My current conditions are a 2006 RMZ 450, Full Yoshi RS-2 Stainless exhaust, twin air filter, Power Now Valve, Boyeson Quickshot, I did have an I-CAT but when I put my bike on the dyno it was showing that the I-CAT was creating too much spark and make the tach go crazy, so I moved it for the time being. I am at Elevation 1500 ft, 35 Pilot, JD Blue dot needle on 3rd postion from top, fuel screw out 1.5 turns, and a 185 main. The bike has instant throttle response and pulls hard all the way through. I did a plug chop test and it is tan low on the ceramic. My question though, does this sound like too lean of a set up? James wanted me to put a 40 or 42 pilot back in and run the red top needle on the 5th position down from top. I tried this and cranking on it right off of throttle created a bwaaah then it would take off. Right now it's instant. I am very pleased with the way it is running, but I dont want to burn this thing up if I am too lean. I have tried everything from a 35 - 45 pilot, both red and blue needles with mulitiple clip placement and 175-185 main jets. Any suggestions?:thumbsup:

if your bike really needs a 35 pilot jet via idle reaction to the fuel screw testing,your needle jet is worn out.

The needle is brand new right out of the JD kit. Do you think maybe my fuel screw could be bad?? the o-ring was torn on it, but i replaced it last night. I think it is working because I am getting different results by turning it.


it is what the main jet screws into.

I understand what the needle is, but I am wondering how it could be wore out if it is brand new??

no,you dont understand.its not brand new.

the needle is not the same as the needle jet.

the needle jet is worn.

Oh, OK, I'm sorry, I see what you are saying now. Now that you mention that, there was very tiny brass pieces in my bowl. I wonder if it could have been from the needle jet?

Is the needle jet wearing out something common?? Would what you are calling the needle jet also be referred to as the Main Nozzle?? I am looking at the exploded diagram, and it looks like that is what the main jet screws into.

main nozzle is just another name for it.

yes,they wear and its common.

The piece JD makes is the Jet Needle, it slides into a "needle jet". I use a .113" drill bit, new, never chucked and slide the chuck end into the needle jet and examine for wear by looking for a dark spot between the drill & hole. This is an area where 1/2 a thousand of an inch is a big deal and like Eddie says yours sounds like it has wear.

I called my local shop and they didnt have any in stock, so it should be here next week sometime. I'll have to check out the needle jet like you said Dave. Like I said before, I have noticed a few very tiny brass filings on the float. I'll take another look at it this weekend. Thanks!

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