I have just received the N1TC needle will fit this weekend. But I don't think it will solve my problem.
Bike pulls really hard down low, and is a bit slugish up top. Now i know it is running to rich up top with the 138 main and airbox lid on, but when i remove the airbox lid it goes like a cut snake up top but a slug down low. Iam running a 38 pilot.
I think that i am getting to much air at low and not enough fuel, maybe a 40 pilot may help.Or will the N1TC cure this problem with the adjustments

Open to suggestions

Running FMF Q4 with powerbomb 138 main and 38 pilot airfuel approx 2 turns out. Running at sea level currently have the NRX1 needle with shim (aust)

 

 

You'll find your bike is actually rich low down (overlap from the raised needle and #138 main jet on the pilot circuit). Solution is to gut the back fire screen, ditch the spark arrestor in the pipe and fit a GOOD free flow after market air filter (eg Twin Air, Uni). You need to give the bike as much air as possible. A good filter does it's job well if maintained well (well oiled and cleaned on a reg' basis.) No need for the airbox lid.
wind the fuel screw in to 1.75 turns. (my current setting.)
Those jets are on the money. #40 pilot will give you trouble. Been there, done that.
Let us know how you go.

With the new needle I would set the height at the same level as the stock item+shim, as a base. Offer them up before you fit to get the setting.

 

westoz I have a twin air filter and have removed spark arrestor will the backfire screen make that much difference.Run perfect down low until airbox lid removed.

 

Hmmm. Try the fuel screw.
Only difference we have is I'm still using the smaller header as I like the low down torque and response it gives. You lose some low end with the bigger header, but gain some top.

 

Have played with the fuel screw but no change. I was considering the bigger pilot as alot of the US bikes use the 40 pilot and they dont have the high flow air box. It seems to run fine until more air is introduced which would decrease the fuel/air ratio.

 

Wouldn't hurt to give it a go. Flat usually means rich though, lean is surge.. Did you try it with the stock #35 pilot?

 

Havnt tried the 35 pilot,that may work Dynojet dont supply a new pilot for there kit. might try to lean out the top end with the new needle and leave the airbox lid on, that way I dont have to pull out the carby again. That Kawasaki service document you posted with the jetting guide. It had the 38 pilot hand written on it was that recommended by kawa or did the local dealer note that.

 

You need to select your pilot based on your fuel screw setting. At good hot motor low idle if you can turn it all the way in and the engine still runs, the pilot is too big.

Same thing if at low idle you can turn it out past 3turns and the motor doesn't cough, pilot is too small.

More reason to buy a extended fuel screw, it not only lets you tune the screw but also select the correct pilot.

Often times bigger pilots than what the above ^ test are used as a bandaid for a needle that doesn't have the correct root diameter. Changing the clip position doesn't change that part of the needle because at low throttle positions your in the straight part of the needle.

Another reminder that when refering to main sizes, or emulating someone else set up. it should be noted what brand jet DJ jets are not the same as oem jets of the same number.

And in addition (sorry I'm on a rant here) when using specs form other models and years, they can often use different airjet sizing so the pilot and main specs don't have the same results.