What needle is recommended?

[yater]

I tried to search but gave up after 3 pages. I'm trying to get things together for the new bike. I'd like to swap the stocker for a new needle but which one?

2000 kdx200
gnarly pipe/power core II silencer
airbox drilled a little and snorkle gone
riding from sea level to 2000 ft.

I'm not sure what jetting the seller has been running but I'd like to have the right jets so I can dial it in quick before x-mas. Can anyone give me a ball park on the main to start with and recommend a needle/position that might work?

 

[BJH]

I don't think there is a correct answer for that. From what I've gathered all bikes with mods have their own special requirements. Do yourself a favor and only do engine mods one at a time. When you get the mods too far ahead of the jetting it's a REAL PAIN to get it all dialed in.
Believe it or not...With your mods the stock needle should be fairly close. Read Canadian Dave's site. It really helps with mods and recommended jetting.

Click HERE and read thoroughly. Then print it out and read it four more times. ;)

 

[yater]

I know, I'd just like to make sure that I HAVE all the jets I may need. The bike will have the pipe/silencer on it. I plan to do quite a bit of riding over the x-mas holiday and don't have a dealership nearby. What about the needle? I know there's a better way than stock

 

[BJH]

That information is listed on Canadian Dave's read decoding the needle etc.

 

[yater]

Yeah, I've read that and understand needles and how they work but was really looking for an opinion based on experience. Maybe someone has similar mods?

 

[m0rie]

If you want to get everything you should get all of the following:

Mains:

158
155
152
150
148
145

Pilots:

45
42
40
38
35

Needles:

BEL
CEL
CEK
CGK
DDK

Between all those you'll have a setup for any altitude/temperature. :-) 'Bout $65-$70 total from Sudco.

-Maurice

 

[cicone]

don't forget to spend about $30 on some Boyesen dual stage "Power Reeds"---you'll be glad you did! :cool:

 

[03KDXHOPPER]

No more expensive than jets are, get a few higher and lots of lower than you already have. The pilot jet is versatile if you adjust the air screw. The main is what you're most concerned about.

My 03 KDX 200 runs a 160 main at 3000 ft elevation 50-90 degrees F. 165 below 40 degrees F.


155 at 10000 30-80 degrees F. I didn't touch the pilot jet or clip position on the needle, and that's a wide range of altitude and temp. All factory, but without airbox lid and snorkel. I haven't finished tuning after the pipe and silencer yet.

 

[Rhodester]

If you like smooth power try a CEL or CEK. If you like snappier power try a DEL or DEK. You'll probably end up in clip position 3 or maybe 4. I'd have on hand a 42 and a 45 pilot. In main jets I'd have 158, 155, 152, and 150....based on the information you supplied. I currently run 152, DEK/3, 42 with air screw at 1 1/4 out @ 80 degrees and 2800' elevation. I have enough flexibility in this set up to just go up or down on the main based on about 25 degrees up or down from that 80 degree figure (and some adjustment of the air screw). I, however, am running a RAD valve which will require slightly leaner jetting than you will need without one. Your riding style will also come into play in determining your jetting as well as realizing that each bike is a little bit different from the next one when it comes to jetting.

 

[Rhodester]

Oh, I forgot to add...I'm running a #7 slide (throttle valve) which effects the needle diameter that you'll need. If I remember correctly you'll need to be leaner by a step or two on your L1 (straight section of the needle) with the #5 (stock) slide (CEM or DEM as an example). Have fun.

 

[farmerj]

Good post, Rhodester. I'd stick my neck out far enough to say that a lot of people are running "in the range" of what you described. I, for one!

Jeff

Oh, yeah - Yater - you're getting good advice on starting points, but you need to experiment a bit to understand your bike and get the most out of your jetting. Even a change in the clip position can influence things quite a bit!

 

[Rhodester]

farmerj, thank you very much! BTW, you're very right about the needle clip position. When I was experimenting with a CEK, in #3 position the jetting was real crisp, but when I went to #4 it was noticeably rich and more sluggish in comparison to #3.

 

[yater]

Thanks everyone! I just got home with the bike and will start on it tomorrow. The jetting is lean right now but I suspect it is still set to stock specs (the bike has a gnarly pipe and power core silencer on it). I have a bog down low that I'll need to correct. I expected that though. I'll probably order 2 sizes up and 2 down (main jet) along with the needles mentioned and start there. I think that 1 size up will work for now since the jetting is rich from the factory. I got back and found a set of tires, skid plate, and carbon fiber pipe guard on the front porch!!! I REALLY missed the kdx while I was without one

 

[yater]

With a performance pipe/expansion chamber, the air box lid removed and the stock or a performance silencer run a 42/45 pilot, R1174K jet needle in the mid clip position, a 152/155 main jet fine tune the pilot circuit using the air screw.

--Straight from Canadian Dave

 

[canyncarvr]

Something to keep in mind that will help you understand needleology: The listed L1 of a needle that is commonly called the length of the straight section is nothing of the sort.

It is the length of the needle from the clip end to the place on the needle the diamter is 2.515mm! That figure is often called the 'magic number'.

Where this is critical is when you understand that a 'C' needle when compared to a 'B' needle will have a longer section of needle that is actually straight (other params the same). Why? Because, the slope being at a greater º, it starts later on the needle to GET to that 'magic number' than the 'B' (lesser slope) needle does.

The length of the actual straight section (again, NOT the L1) is a huge tuning factor in circuit transitions, and those transitions are a big deal in the kdx.

But then....if only three pages of reading wore you out....you likely aren't too concerned about it? That would be too bad. :(

 

[yater]

Again, this is my 3rd kdx but it has been years since I've adjusted the jetting on one. I have 4 bikes and understand jetting and know how to read. I'm trying to get the bike ready for this coming week so I can ride. Luckily, CD spelled it out and I went with his suggestions. The reason I posted was because I did NOT have the bike yet and wanted to have things ready when I picked it up. I've got her dialed in now and I'm ready to ride. Thanks everyone--if you want to keep reading the jetting page, go for it...I'll be riding

 

[canyncarvr]

What I said wasn't to be taken as a gibe.

Understanding the carburetion process will hold you in good stead no matter what bike you ride. Jetting by 'the book'...if that means doing what someone else has done, or by doing what someone else says to do.... isn't going to get the job done very well.

CDave's recommendations are ballpark....and small changes say, in the variable orifices, can make a big difference.

Have fun riding!