Needles

[jowens66]

I am running the stock needle in my KDX 200 and was wondering if i change the needle if it will smooth out the power deliever. What does changing the needle do? I am looking to smooth out power and make it more torquey. I ride in 1-3rd gears all the time. Steep hill climbs are what i ride on most. Would a DEK be best? This is going on my stock carb, but i am about to send my carb to Mr. Black and get the works done on it.
Thanks

[Indawoods]

You would need a DEL needle. DEK is for a modified carb.

[canyncarvr]

Re: 'and was wondering if i change the needle if it will smooth out the power deliever.'

'Smooth' may be a matter or interpretation. A correct (what works for you) 'D' taper needle will improve the response of the lower end of things, but I don't know that I would say just a needle change (a 'D' slope) would be 'smoother' than the OEM needle.

Ron's carb work will go a long way toward making the bottom end of a KDX (especially a 200) work better.

A modified 200 will work with the OEM 13T CSS a lot better than the stock KDX will. Are you using a 12 or 13CSS? Well...or some other combination of teeth front and rear?

You could advance your timing a couple ºs.

If you end up ordering a fistful of needles to try...a BEM is something to think about. It's smooth. Boring....but smooth!

[jowens66]

I have a 12 tooth css and a 50 tooth rear.
I am about to send my carb off the Mr. Black along with the head and let him work his magic.
You speak of advancing my timing, how do i do this? Sorry for the newby question, but i appreciate all the help and answers.

Thanks

[canyncarvr]

Re: 'How do I...'

Looking at the rotor from the rotor side (LH), you can see (with a kick) that it moves CCW when the engine is running. Movement of the sparky coil (the one on the bottom of the stator that is potted btw) in a CW direction will cause the timing of the engine to be advanced. The trigger point on the rotor will hit the coil sooner.

The rotor (flywheel) needs to be removed to get TO the bolts/screws holding on the stator.

Generally (not written on the tablets Moses brought down):
Advanced timing=better bottom end
Retarded timing=better top end

Don't advance it more'n 2-3º..well, unless you know what detonation is..and that by the time you HEAR it, it's too late!

BUT!! 12/50??!!

IMO and all...but that is TOO LOW a final drive. At some point there is a balance point between too low (wheel spin and looping things) and having the bike PUSH against something...and 12/50 is well past it. You will go farther with the latter (the push part) situation. Of course...your bike has to RUN 'down there'..and therefore we have 'the mods' riders muck around with so much!

[jowens66]

I too thought 12/50 would be too low, but it is perfect for the terrain i ride IMO. 12/47 was a bit too high and 2nd gear was too fast for the riding i do. Now second gear is the gear i stay in the most, probably 98% of the time. Speed means nothing where i ride.

I may try to advance the timing on my bike. It sounds like just a little too much advancing can really mess something up. Is there any visual guide online to doing this? Thanks CC, again you come through with some great info.

[canyncarvr]

Re:'visual info..'

Just 'cuz math is fun...


Figure your stator plate at some inches (call it six for this discussion...I don't exactly recall what it is exactly).

Now...cornbread are square and pie are round so it's a good thing we don't need to know the area of nothin' (Pi x R-squared), but Pi x D gives you the circumference....or 18 3/4+" in this case. 'D' is the diameter.

Divide by 360...and find that .050" gives you a single º.

'Thar 'ya go! Make a change at the outside of the stator plate of 50 thou and you have one degree. Make a mark or use the centerline of the case as a reference.

Measure the stator plate to plug in your own equational startistics. And...check the math in general 'cuz I ain't never right the first time...I am the fourth time, though (THAT is a joke ain't NOone gonna get! And those that GET it won't agree..but I know WHEN I'm right!!)

Oh...Pi is 3.1416...and don't no one argue about the unrepeatedness of the value, K?

BTW...Pi is the relationship of any circle's radius to its circumference...well, actually its diameter (2 x Pi x R works too! It's associative by golly!!) but anyone can divide or multiply by TWO!

Another btw...but don't let anyone tell you something is a 'perfect circle'. It either IS a circle (perfect) or it ain't!

It (whatever) may be 'circular'..but 'circle' means only one thing....all points equadistant in a plane from a given point (uh..that would be the center).

On two axes? That would be a sphere...but spheres ain't circles.

Class dismissed!!

Oh..yet more byes the waze... Above I mentioned moving the exciter coil. To be clear, you move the entire STATOR, not just the spark coil. The light coil doesn't care where it is. Your lights don't run at 15ºBTDC better'n anywhere else.

[jowens66]

CC,

Are you a math teacher? lol. I just got a whole leason (refreshment) but i hadn't even thought about that. Good points. I'm gonna try it out. How much more bottom end would advancing the timing 3 or 4 degree's give me? Thanks CC.

[scheckaet]

I feel like i'm going in circle or is it "circular pattern? I don't know anymore
my head hurts

[IdahoCharley]

CC of course is correct in a methodology to determine the distance to move the stator plate but for reference sake - there is an easier way.

The is a machined line on the movable stator plate and a pair of corresponding lines on the backing plate which represent the factory's allowance for acceptable range of ignition timing. Look at where the stator plate mark lines up now compared to the two lines, loosen the stator plate and adjust the reference stator plate line to the most advancing factory spec'd line, tighten down the stator, replace everything and and give it a try.

[jowens66]

Excellent info guys. Much appreciated.

[canyncarvr]

Yes.....


'I advanced my timing some unknown amount and it really runs great!'

'How much?'

'The maximum allowed by law...and of course...but the Mr. Kamuzuki that put the marks on my plate thing. Other than that, I don't know.'



Re: how much better

Enough that if you don't notice a significant difference, either Mr. Kamuzuki made his marks real small that day....or something else is wrong with your bike.

There is a bit of a rub. Generally speaking, more advanced timing to help the bottom part of things subtracts from the top end of things...and vicey versa.

[jowens66]

I have read that retarding the timing actually smoothes out the hit of the bike, while advancing the timing gets the power band in faster. My bike is geared plenty low, the smoother i can get the hit, the better. So would i want to retard it or advance it?

[jowens66]

Another question. Does anyone run a EEL needle? Not much reading to do on them. CC what is your input on the eel? I read where it really smooth's out the power delivery, almost makes the motor feel electric. I'm leaning torwards the D or E needle to smooth out the hit of my bike and maybe retard the timing a bit. The bike is geared nice and low and if retarding won't take much/any away from the bottom end then i would do that to smooth out the hit. Suggestions?

[canyncarvr]

Retarding the timing will retard the lower-end performance in most cases, too. I thought you wanted it BETTER in low-end stuff?

In any case, you are correct in the 'hit' part of things. Not that the KDX is particularly noted for the severity of its gobs-of-ponies hit...

I tried an 'E' series needle. My personal opine is 'yuk'.

Your mileage may vary!

[jowens66]

What needle do you recommend for smoothing out the hit cc? A B taper or the D taper? What is the stock needles taper? Sorry for all the questions.

[canyncarvr]

The stock needle is a 'B' taper. The 'H' needles are in the BFQ area (I didn't check that..but it's close).

I'm not Mr. Jetman..and I wouldn't pretend to tell you what you will like the best.

JD (James Dean) IS Mr. Jetman..and he said in regard to the KDX OEM jetting, "It is the stock jetting that is odd." He also said, "..it is hard to tell until someone rides and tests."

My point of view comes from needles I've used on my bike...but the modifications of my bike, what I prefer, and where I ride are obviously not the same as your situation.


It's not ONLY the taper. Keep in mind that a 'D' taper will start 'later' on the needle, and that may translate into 'smoother' because it happens at a higher throttle (maybe more speed) position.

I know a 'C' with the corresponding diameter and L1 that fit my bike hits too hard and too soon for me...but it's fun once in awhile. The 'D' is considerably less aggressive than is the 'C'.

But...the BEM I tried was very tame..a combination of low slope angle and larger diameter.

The best way for you to tell...is for you to tell. Experimentation with different needles will give you a good 'feel' for how they work..and with that knowledge YOU can choose what suits YOU. I've been through a good dozen needles to get to what I ride now (DEK). But, as said, I know what to expect with 'A's 'C's 'E's and 'B's...only because I've tried them. Depending on the riding conditions and where I'm going to be riding, I may change the needle just to suit myself.

Ask any question you like...but an exact answer isn't what you will likely get. And if I DID give you one...you probably wouldn't like it anyway!

Ron will probably send your carb back with a CEK. Order a handful from him (cheap fun) and sort out what you like. Certainly a DEK and a BEM for starters...maybe an EEK, DEJ.

Forget 'A' needles. They're DOA.

Are you familiar with JD's spreadsheet? You can put in any needle combo you want with pilot, main, slide cut, temp, and el. and see a graphical representation of needle profile and % fuel delivery change. It's a great tool for 'seeing' what your rear end felt from a test with a particular needle. Google should find it for you. You need MicroSoft Excel to use it.

Have fun!

[RBD]

Another question. Does anyone run a EEL needle? Not much reading to do on them. CC what is your input on the eel? I read where it really smooth's out the power delivery, almost makes the motor feel electric. I'm leaning torwards the D or E needle to smooth out the hit of my bike and maybe retard the timing a bit. The bike is geared nice and low and if retarding won't take much/any away from the bottom end then i would do that to smooth out the hit. Suggestions?

I have found that a EEK needle is a great needle for a 250cc 2 stroke single cylinder engines in the sand at the beach....., not so sure it would be a good needle for the average KDX 220's and 200's riding conditions

Thank you,
Ron

[jowens66]

Much appreciated CC. Pretty well answers all of my questions at this time . Thanks to you too Ron, im going to be sending in the carb and head soon. Thanks for yall's time.

[canyncarvr]

Ron: I tried an EEK, but not an EEL. I recall I didn't care for the 'E' needle, not the specifics of why I didn't...but I didn't!

Now THERE'S some helpful information for 'ya!