KDX 200 modifications

[kdxracer577]

i have a 2000 kawasaki kdx 200. so far i have an fmf burley pipe and powercore 2 silencer, v-force reed cage, uni airfilter, 48 tooth rear sproket (47 is stock), a spiralmax unit (it swirls the air before entering the carb for a better air fuel mixture), and the airbox lid was removed. i plan on getting cylinder porting but am not sure what that is. is porting the same for all dirtbikes or can i have different things done to it for different power results like more bottom or more top?? and i would like to know if there is anything else i can do to my kdx to make it more powerful (its my project to make my kdx as fast as a 250), other than boring it out or using higher compression (i still want to use pump gas (93). thanks for any info.

 

[woods_rider1]

I put way too much into my KDX and had all of the same mods as you do, and I can tell you it didnt have anywhere near the power of any modern 250. A friendly suggestion might be to save your money trying to make your bike into something it isnt and use that money toward the 250 you are seeking. While I had my KDX 200 I enjoyed it alot, but the switch to a modern 250 (only 50cc mind you...) was night and day. I used to switch back and forth with a KX 250, RM 250 and my current KTM, and there was absolutely no comparison in handling, suspension, power delivery etc.

 

[little jeff]

KDX Racer, I had a hopped up KDX220, 02' model. Did all the hop ups like porting, carb mods by RB Designs out of Portland Ore. reeds, uni filter,etc. But like it or not the KDX is not a MX bike. Do your self a favor, if you plan on spending all that money on your KDX, use that money to buy a KTM 250 or 300 like I did. You won't regret it. I'm not saying the KDX is a bad bike, it is a awesome woods bike, but if you want more power, get a 250 or bigger.
Just my opinion
Little Jeff

 

[shr]

Note! any porting that in evolves exhaust or intake opening enlargement. The cylinder needs to be re-plated.

If not, after awhile the plating around the ported openings will start to flake away. And this will cause engine damage........

I've seen it before and serious engine builder know what I mean.

Clean up of intake, transfer. and exhaust passages not involving actual port openings to cylinder port holes will be good and help over all flow, thus a little more power.

 

[CaptainObvious]

In the same sentence you say that you want to be as fast as, and as powerful as, a 250. The two are not the same. If you are looking for pure speed a sprocket change (14/45) will have a huge effect on speed, but it will have a negative effect on acceleration.

What kind of riding do you do? If you are a woods/trail rider the size of the engine really doesn’t matter, it’s the characteristic of the power delivery that matters. The KDX does well in this environment and the changes you have made, along with the added benefits of the porting, will make your bike as fast in the woods as any KX/YZ/CR/RM.

However, if you want a competitive MX mount the KDX is the wrong bike. Like Jeff said, it’s wasted money to try to turn your KDX into a competitive MX machine. Not only will you need the engine modifications, but you will also require significant suspension modifications as well.

When someone tells me that they want an MX bike that is good in the woods (and vice-versa) I usually tell them to spend have as much on the bike they want (buy used or a few years older than they planned) and get TWO bikes: one for MX and one for the trails.

So what are your actual objectives with this bike?

 

[KelvinKDX]

kdxracer577: I agree with what the others have said. If you want to have an MX bike - get an MX bike.

I have done all the mods that i plan to do performance wise and am happy with my KDX200 (which is now 225cc). Eric Gorr did my cylinder head bore/port/plate and i would recommend talking to him about what you are seeking. I definately have more low end and top end power.

Will i get another bike - of course (this $$ keeps burning a hole in my pocket and i'm addicted to dirtbiking even though i am one of the worst riders around). :confused:

I mainly ride woods. I do not ride MX and can prove it if you put me on a track! :(

anyway - like i said - talk to eric http://ericgorr.com/

 

[RTL]

As usual, the DRN KDX guys are spot on. The KDX, IMHO, is a great off-road machine. In stock form it is a fun playbike and with a few mods it can quickly be transformed into a more competitive off-road machine. In fact, with a few mods, I would venture to say that the KDX's performance can exceed most weekend warriors abilities in an off-road environment. Did I mention off-road?!

577, I have found that most KDX riders I run into utilize the playbike aspect of the KDX. In fact, most of them do NOT acquire basic tuning skills such as proper jetting and basic suspension/bike setup. Your comment regarding porting and your desire to hop-up your KDX to posses 250cc comparable power leads me to the following questions:

1 - Do your ride off-road, MX or possibly both?
2 - How experienced of a rider are you? Beginner, Novice, Old pro?

Now, with all that being said, let me next mention that I live in an area where there is off-road and closed course opportunities. I have my KDX power delivery setup for tight trails (4 stroke like bottom) with a semi-smooth mid hit. This allows me to ride the tight woods stuff while still being able to exit a pre-double jump berm with enough speed to clear the small to mid sized jumps. In addition, I have revalved both the front and rear of my KDX in order to allow me to venture into the woods and onto the track with simple clicker modifications. Note that this is a comprimise by choice on my part, as my KDX could be valved to be optimal in the woods (much plusher). MOST choose to setup the KDX for the woods, and not to comprimise since they do not venture into the MX world. Get the picture I'm painting here? Also note that the KDX setup strickly for the MX track is still not going to perform equally to most 250 MX machines.

Your 200 has rev style porting as delivered stock so I would heed the advice of KelvinKDX and let Eric address your need for more power. I would also seek the advice of Jeff Fredette, he helped my with my setup which may or may not be what you are looking for. Bottom line, your KDX can be setup to allow you to have fun in the woods and on the track, but it will be impossible to setup the KDX to work optimally in both worlds. Also, IMHO, the KDX can be modified for the MX world but if you plan on spending most of your time on the track purchase yourself a motocross machine as you will be much happier in the end. Good luck and let us know how it turns out. :thumb:

 

[gooby]

There isn't one more damn thing anyone else can say, to say it better than RTL said it .:)

 

[hab]

Here's the deal... I have a 2002 KDX200 (my second KDX) and the only mods I have done are the snorkel removed, jetted, FMF Rev pipe and silencer, and stiffer fork springs. The only "mod" that I cared about is the jetting and the fork springs. Someone actually traded me the FMF exhaust for my stock exhaust. I live in Colorado, so jetting was a must. The fork springs I did was because the stock springs are too soft. Other than that, the rest is all rider. I ride with a bunch of guys: XR600, 2 x XR400's, WR250F, XR250, and KDX220. I am better than all of them except the guy on the XR600 and I'm catching up to him. So maybe instead of concentrating on making our bike faster, we should concentrate on making our abilities better.

 

[KelvinKDX]

So true.

 

[Braahp]

A buddy here thought he needed an ultra horsepower bike and acquired a YZ426. He races B class hare scrambles. Well to make a long story short he switched back and forth and his laps times were always much better on the little ol' KDX 200.