kdx compared to 250's?

[upnorthbacon]

How does the power of the kdx's compare to stock 250 mx bikes? I'm trying to decide whether to buy an mx bike and convert it for off road use or buy a kdx? I will be riding with 450 thumpers and I want to make sure I can keep up when we hit stretches of fire roads and such. It will mostly be single track type stuff but there will be times when we ride two tracks and fire roads to get places as well. I previously had a wr250f a couple years ago but sold it. It was perfect for the single tracks but I was really revving to cruise with them between trails and on the fire roads. I don't think I would step back down to a 250f after riding with them a couple years ago, I'm on a limited budget now so whatever I buy will be used. I like two stroke bikes because of the cheap rebuild costs, especially since my budget is low and I'm buying used.

 

[mudpack]

Of course, the KDX200 is noticeablly short of a KX/CR/YZ 250 motocrosser's power.

That said, don't worry about the 200 not being able to run with Open class bikes on the trails.....it can if you are up to it; it ain't the bike anyway, it's the RIDER!

If YOU can run with the big boys, it doesn't matter what size bike you are on. If YOU aren't up to it, you won't be any faster on a 450. Your (our) speed limitations aren't located between your (our) knees, they are located between your (our) ears. Seriously.

 

[2448stuart]

Your looking at about 12 to 15 hp differance between them.Imo I whould go for the mx bike It's also lighter which will help on the single track and you don't have much chance keeping up with the 450s on the fire road's on a kdx.But be careful a 250 2t mx bike is a big step up from a 250f.

 

[upnorthbacon]

I just don't want to be screaming at the redline in open area's while they are cruising along. I'm confident ill be fine in the trails, I just want to make sure it's geared tall enough and has enough top end to cruise a few miles at higher speeds?

 

[2448stuart]

Well 250 mx bike's are fast but they tend to be geared low for track use but you could gear it up but then you will lose abit of top end.

 

[upnorthbacon]

I guess I'm looking for info on gearing rather than power. Will I be able to cruise comfortably with say a wr450, or are they geared a lot taller up top?

 

[2448stuart]

Yeah they are gear a fair bit higher.A 250 2t will do about 75mph flat out give or take abit.

 

[2448stuart]

Here is a vid of my 89 kdx 200 bored to a 240 vs my brother 89tt350.The kdx is the one on the right. http://www.youtube.com/watch?v=01UIYI2f0cI have look and see if you think the kdx is for you.

 

[mudpack]

I don't notice much difference in top end speed between the KDX200 and the KLX450R.
Neither one will come close to 75mph, and I doubt a stock 250 two-stroke MX'er will either; they are geared too low.

 

[upnorthbacon]

I'm not looking to race them. Does the kdx cruise comfortably with th klx in 5th gear? What I don't want is to be screaming for a few miles while everyone else is chugging along comfortably.

 

[KTM Mike]

Yes - the KDX will cruise fire roads just fine. MX 450s will have comparatively short gearing. If you find you want more top end for road use, drop the rear sprocket size a couple teeth. The KDX will be dramatically better suited for the single track use than the MXers will be unless they have been seriously worked over to set them up for woods. Where is your priority - the single track, or the two tracks? Not that it is an issue, but anyone can go fast on an easy two track.

 

[2strokesrock]

The KDX has a six speed trany..so it should do just fine. The top speed on just about every dirt bike is 75 MPH and the kdx will do 75 but not vary easily.
unless you are rideing bajas with XR 650s I would not worry about it.

 

[OLHILLBILLY]

KDX should actually do better than a 250MX bike on open fire roads given it's 0.870 overdrive top (6th) gear compared to the MX bikes somewhat underdriven top (5th) gear.

 

[mudpack]

I'm not looking to race them. Does the kdx cruise comfortably with th klx in 5th gear? What I don't want is to be screaming for a few miles while everyone else is chugging along comfortably.

How high do you think 450's are geared???
As I said before, I don't find that much difference between the comfortable top speed of the KLX450 and the KDX200.

If you are looking to cruise comfortable with the group on the fireroads, the KDX will "cruise" at the same speeds as the KLX450R will cruise at.
I don't see you at any top speed handicap with the 200....I know I'm not and I ride with KTM300's. and WRF450's. We aren't racing each other, either, just maintaining a brisk pace.

It's hard to say if you will be left behind on a KDX200: I don't know who you ride with, and their mindset. If they are good, and want to leave you behind, they will....no matter what you are riding. If you are good and want to stay stuck on their rear fenders, you will, no matter what you ride.

I can't stress enough: it's not what you ride, it's how you ride it. Most bikes are far faster than their riders.

 

[dirt bike dave]

For my purposes, top speed never mattered much, as I mainly ride single track and rarely get over 45 mph, even top gear on mountain fire roads.

In my experience, most 2 stroke 250 MX bikes will top out around 60 mph and are limited by the stock gearing. A KDX 200 will pull low 70's with enough room.

Many 4 strokes will rev quite high if you have enough room. When geared up for the road, my old XR277 with a few mods would eventually get up to over 80 mph on asphalt.

 

[Dixie4]

Yea you will be fine, I ride alot with guys on 300 and 450 and leave the 450 in the woods and have to wait on them was going to get a KLX 450 But you can't beat the 200 for all around riding.

 

[sr5bidder]

I have to agree with mudpack this time and that I don't know what 5th and sixth gear is ..I may have been in them at one piont on the dirt drags.
If your buddies ride 450 4 tokes why don't you just get one or do you not like 4's.

the pluses for the kdx are its great in the tight stuff, super easy to start hot or cold and also a lower maintenance machine as compared to hipo mx bikes.
the negetives are (as compared to the 4 strokes I've had) rear wheel spin and not as much trackable engine brake

 

[steve.emma]

its much cheaper and easier to convert a 250 2t mx bike into a woods bike than it is to upspec a kdx into a faster better handling machine. i know because i have tried both if these routes and the mx bikes come out tops. as far as top speed goes just play with gearing until you are happy. gearing it up to gain more top speed also has the added bonus of reducing some of the 'hit' that mx bikes have that can make them tricky to stay on sometimes.
dont get me wrong here, im not bagging the kdx in anyway but it is what it is. basically unchanged since 95'.
if neither of these sound good to you then why not consider a modern purpose built enduro 2t like a ktm exc or a gasgas?

 

[2448stuart]

its much cheaper and easier to convert a 250 2t mx bike into a woods bike than it is to upspec a kdx into a faster better handling machine. i know because i have tried both if these routes and the mx bikes come out tops. as far as top speed goes just play with gearing until you are happy. gearing it up to gain more top speed also has the added bonus of reducing some of the 'hit' that mx bikes have that can make them tricky to stay on sometimes.


I have to agree with steve.emma on this one the mx bike setup for off road will be easier, cheper and faster than the kdx.Not to say the kdx is bad but like steve.emma said it is what it is.

 

[2448stuart]

I don't notice much difference in top end speed between the KDX200 and the KLX450R.
Neither one will come close to 75mph, and I doubt a stock 250 two-stroke MX'er will either; they are geared too low.


I raced my mate on his 01 yz250 stock gearing and my speedo was reading 120kph.And the top speed of a wr450f is 89mph on the revlimeter which was tested in a mag I was reading.

 

[2448stuart]

Even my brothers 89 tt350 was clocked at 85mph and it was 1 thooth down on the rear sprocket from stock gearing.

 

[mudpack]

I raced my mate on his 01 yz250 stock gearing and my speedo was reading 120kph.And the top speed of a wr450f is 89mph on the revlimeter which was tested in a mag I was reading.

Even my brothers 89 tt350 was clocked at 85mph and it was 1 thooth down on the rear sprocket from stock gearing.

The more I learn about speedometers, the less I believe them.

That WR450F's top speed was calculated, not observed.

The OP's question was along the lines of this: will a KDX200 keep up with the 450F's on a fireroad. In my experience, the answer is yes, the bike will. Whether the rider can is, of course, an unknown.

 

[dirt bike dave]

In terms of top speed, yeah, the KDX should be fine if you wring it out on a long enough straight.

But high speed accelleration is where the 450s will eat up a KDX. On a curvy smooth high speed fire road with 30 mph corners and 60+ mph straights, the 450 will pull lengths on you every single time you need to accellerate from 30 to 60.

 

[2448stuart]

The more I learn about speedometers, the less I believe them.

That WR450F's top speed was calculated, not observed.

The OP's question was along the lines of this: will a KDX200 keep up with the 450F's on a fireroad. In my experience, the answer is yes, the bike will. Whether the rider can is, of course, an unknown.

I agree that the kdx will keep up but upnorthbacon said he use to ride a wr250f and did not like the fact that it was reving to hard to keep up and i don't think the kdx whould do any better.Say his mates are cruising on there 450s at 100kph down a open fire road the kdx will be reving pretty hard to stay alongside them.

 

[thelonesurvivor]

take it from me...i have a kdx 200 and a yz250. the yz is geared lower than stock so it can be a good woods bike. having that been said, my yz will rocket from 3rd-5th but it hits its top speed within a few second. seriously it hits its top speed (well close to..i dont over rev on it) very fast. my kdx has never gotten near its top speed. compared to my yz; acceleration sucks, top speed is way more. this is due to the fact that the yz is a 5 speed basically. if u want to keep up with them, get a 250 mxer, put a pipe, silencer, v-force reeds, and a new top end and it will be a great bike. also the suspension on a kdx cant compare to a mx bike even when the kdx has new springs. the only thing i can say is better on the kdx compared to my yz is the headlight.