Just got back from the 1st big weekend with the 400. We put in the dynojet kit, e-series muffler, removed the lid, and slapped a 13t on the counter shaft.

Quesiton:

The plug was bone white with the recommended jetting and I ended up swapping out mains all the way up to the 155 that came in the kit and then went beggin and borrowing DJ mains up to a 165 which still resulted in a bone white insulator. I had a CRE8 plug in my toolbox and after dropping that in I got a nice tan burn indication. Are you guys getting a really lean indication with the DJ recommended setting as well and is anyone else using a 8 heat range to remedy this lean condition?

Also, does anyone know why the KFX DJ kit only includes up to a 155 mainjet when the Z version comes with up to a 165 main; doesn't make sense to me.....

Thanks in advance.

Rich

 

I have the same set-up(MBRP slip-on) and I run a DJ 160 main with the stock plug and everything is fine, runs great!!

What do you have the needle at and the mixture screw? Just curious..........

 

Needle is at 3 and the FS is 3.5 out. It seemed to run ok with the 155 i.e. no real hesitation or popping but like I said the insulator stayed bone white even after running a DJ 165 main (until I put an 8 plug in). Some lady @ DJ said that you can't go by the plug because pump gas has additives in it but I say B.S. cause every other off-road toy I own is jetted by the plug, feel, and manufacturors recommendation (at least for a start point).

I still don't get by DJ sell 2 different kits between the Z and KFX and why the mainjets that come with them are diffrent as well??????????

 

have you checked the plug at 0-1/4 throttle,1/2-3/4 or just wide open?

 

No I didn't take individual throttle plug readings. IMO it was not warranted because it was not popping, hesitating, or burbling anywhere within the powerband. The insulator was bone white after getting back from 10-30 minute rides over a wide variety of throttle positions. I'm not a newbie, I've been down the tuning road many many times with both 2 and 4 strokes.

Like I said, it was running pretty well with any of the mains I tried (150-165) but when an insulator is that white after long rides that tells me it is burning too hot. When I dropped down to the 8 plug in it was a nice tan color which is what I'm after but I just thought it was funny that I hadn't seen anyone post that they had to drop to an 8 especially when you figure I'm not even using a K&N or similar "high flow" filter.

 

Have you tried calling DJ back and getting someone elses opinion there, hopefully you wont get the same person again!

That is odd that they have 2 different jet kits.

 

Guess I'll have to pay them a visit (drive by close every day) even though I have a feeling that'll be there standard story i.e. the additives in gas thing. It'll probably be a good thing though because I can't understand why they have 2 diff kits for the Z and KFX and I'll get to ask them about that in person.