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SPUTTER

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Posts posted by SPUTTER


  1. Sometimes, if it acts overly rich, it is - but not from jetting. After checking out ignition issues, you may want to swap carbs with someone and see if that fixes it. I had purchased a KDX220 that misfired (acted like rich) on top and would not rev out cleanly (sounds a lot like yours)- it turned out to be a bad carb...sometimes an air passage gets blocked internally - rare but it does happen. (I've read of others with that issue too - a bit of carb metal lodges internally-impossible to find). I had completely torn the carb down, including the jet block, ran wires through everything, compressed air, etc. As soon as I swapped out the carb it ran perfectly.

    The previous owner had gone to great expense trying to lean out the carb, but nothing worked. The piston and head looked brand new, shiney and clean from too much fuel. Try running it out of gas and see if it revs up higher before it dies as it runs out of fuel.


  2. regarding the bar-brace, you may be able to use the original bar brace with careful bending so it clears the damper. I've done this - the main thing is you want to make sure it is a large radius bend (bowed) so you don't create stress risers - then you can scoot the clamps slightly inboard a bit to make up for the reduced length. If you do it carefully the brace will be just as strong other than the reduction due to the new bowed force vectors, but it will work fine. Renthal did or does still make a bar with the brace bowed to clear the damper, and I'd bet your salary that they bend it cold too.


  3. Yes, they fit very well in a KDX chassis. I had an 08 KLR650 that was a pig off-road, so I decided to put the torquey engine in my 97 KDX200 chassis. It needed just a few modifications, heavier fork springs and such, but all in all it only took about 6 or 7 hours to do.

    I now have a great offroad torque-mobile that can handle anything including supercross tracks. If I had that bike setup back in the day I would have won harescramble overalls instead of being an also-ran.

    One thing I decided to do was use the KDX dual radiators as the KLR only has one, and with all that power being used to its potential off-road, I figured it needed all the cooling it could get.


  4. I agree with getting an F model. Lots more fun, lighter, more HP and the yamaha F's are pretty solid for valve reliability (unlike the hondas). The WR250r is down on torque in the lower to mid rpm ranges and struggles to lift the front end at lower speeds without a lot of body english.... the F model is a wheelie machine. (I've owned 2).


  5. The bike is heavy. If you get in a situation where you need to lift it, you might be in trouble unless you're built like Conan the Barbarian. I enjoy my ride for fireroads, single track that isn't too technical, and so on, but I won't take it on really technical stuff where I take my full-on dirt bikes - even if I don't have to lift it, it just isn't much fun under those conditions.

    Also...if you are an aggressive rider, the stock rear suspension is screwed up. You'll need to get it revalved to make it work right - usually a couple hundred dollars. So, a street-legal dirt bike (like a plated WR250F) might be better for where you ride.

    Where the WR250R shines is versatility, it is pretty good on the highway and handles most dirt chores fairly well.


  6. For a rough estimate of spring matching your weight...when you set the sag at 4" the spring should be compressed between 3/8" and 3/4" - if less than that the spring is on the stiff side for your weight, if more than that it is probably a bit soft - . One thing is to set the sag at 4", ride in the kind of terrain you frequent and then you can adjust for more or less preload. I usually end up setting sag on my KDX's a bit more than 4", as the action seems better through stutters and such (which I always ride a lot of) with no reduction in steering ability. i have no idea why there's a line through all my typing...LOL...


  7. Adding oil through the top would not cause the problem you describe - it could be something as simple as a broken spring.

    Working on forks isn't hard at all IMO - I do it all the time with no special tools, just an impact wrench and the allen to spin the compression stack out. There are plenty of videos on youtube on fork maintenance -

    You won't know what you're getting from ebay either, who knows what's been done to someone else's forks - spring changes, revalves, pitted lower tubes and general wear. Not the way to go unless you're taking them apart to rebuild and setup anyway.


  8. LOL, the wife rules!

    Around here the bikes value would be similar. Some guys try to get more for the KDX's but in my opinion condition rules the prices on both models.

    My last KX250 was a 2002 and I sold it and kept a KDX200. I had revalved the KX suspension and stuck a flywheel weight on it, but still always seemed to choose the KDX for trails. The only reason I kept a KX250 was for the occasional hare scrambles, as the KDX was more fun and handled trail riding better. I still push it sometimes tho' so I always recommend aggressive riders upgrade the front KDX suspension - I always stick a set of USD's on them.

    The KDX has a more comfy seat, the rear shock is off-road valved, the six speed will keep it in the engine's sweet spot, the chassis is short so it has the potential to turn on a dime if it's set up right. I love the dang things. If the bike doesn't already have it, get the FMF woods pipe.

    Check out Fredette's website for a discussion of what mod's you might want to do, including spring rates.

    Have fun!


  9. Besides the stack, what is different internally from the YZ to KX's? Aren't they both 46mm KYB's? I never had any luck with the Kawasaki KYB's but I have a bone stock 02 YZ125 that feels great.

    As far as I can tell the stack, actually more specifically, the base valve itself, is the real difference performance-wise. I had set up a KDX with KX500 forks and I couldn't get the smooth off-road action I wanted no matter what I did with the valving shims. So, I stuck in a set of 04 YZ250F valves that I had (also re-shimmed), and immediately got rid of the harsh hits that were beating me up - so the KX forks were OK other than the stack ass'y. Basically, thats what race tech's gold valves do - allow more flow beyond the shimming end of it. Comparing the KX base valve to the YZ base valves, the YZ valves have larger porting and an additional lower port. The WRF base valves have even more flow - quite a bit more - I'm setting that up for my 220 for rock gardens.

    I have never taken apart the cartridges at the same time to compare the yamaha KYB's to the Kawi KYB's so I don't know if the internal valving is different there.


  10. Going back further, I used to ride RM400's (79,80) and they put out about 36-38 HP - I still ride the same trails today and my good running KDX200 actually pulls some of the uphill trails better...it puts out about the same HP but with power valves has a longer flatter torque curve (and one more gear). The RM400's would tend to have to big a gap between the upper gears for some situations - if you couldn't keep it on the pipe you lose. After power valves were pretty much figured out by the manufacturers, I haven't seen much difference in 250 power other than that smoothing-out effect to get more torque over a longer rpm range. One of my favorite bikes, power-wise, was an 89 KX250 I had. Big mid-range with good off-bottom. I had no problems keeping up with anyone while I was still racing it in 2002. The 96 WR250 I have (YZ engine with wide ratio box) feels a lot like that old 89 KX.

    • Like 1

  11. knurling is a machine shop method of expanding the metal - like the handle of some tools. I do my own, but any machine shop can press out the stems from both the "new" triples and the kdx triples, check the relative diameters, knurl the kdx stem if necessary, and then press the kdx stem into the "new" triples.

    The whole thing shouldn't cost more than about 50 bucks, I would think.


  12. The KX500 is the simplest, but the forks aren't the best - even if you carefully revalve the valve stack they are fairly rough off-road in most tough situations.

    The open-chambered yamaha forks (pre-2005) are easily tuned for off-road and depending on your weight/aggressiveness you can use different years to get the right spring set for you. I currently have 2 kdx's with yamaha usd's and each is tuned for different kinds of riding. My 200 uses 02 yz125 forks with the stock .41 forks for more aggressive riding, and my 220 uses 04 YZ250F forks with .39's for rough single track stuff. I think the yamaha forks are more easily tuned for off-road than the KX's as the yamaha compression stack base has more flow capability.

    The yamahas are an easy conversion. You will need to knurl the stock KDX stem a few thousanths to get a press fit in the yamaha triples (just like you would with most KX triples). The KDX caliper will work, but you will need the yamaha caliper mount bracket. The yamaha fork guards have plastic brake line guides which I use to clamp the brake line to with mini hose clamps. You will also need to widen the KDX stops by simply welding a wider bracket right on the top of the old kdx bracket. I recommend the 2001 and later forks as the triples move the handle bars about 1/2" further forward than the original kdx location, which makes the bike handle soooo much better.

    I use a yamaha wheel on one bike and a KX wheel on the other - if you use a KX wheel you'll need to custom make the spacers. Pre-2001 yamaha wheels use a smaller diameter brake rotor so they won't work as is.


  13. Not many specifics so far are there?

    My experience is that outside of suspensions that have evolved for motocross or supercross, there isn't that much difference or improvement. The engines produce similar horsepower over the last two decades - the late nineties bikes were getting pretty smooth with the power valve designs and could always be tweaked with the right pipe/jetting combo. Braking is pretty much the same, but varies some from model to model. Off road suspensions are just a matter of tweaking also. I actually prefer the old open chamber design for off-road use - I can get them dialed in easier. I've owned and ridden many late model bikes, and I've come to the conclusion that for off-road use, the older bikes are every bit as good as the newer ones - you just need to modify them for your level of riding and terrain encountered. Let me put it this way, you can modify an older bike to perform off-road every bit as well as a new bike for one-half the price of a new one. MX is different at expert-pro levels, but for the other classes, money could be better spent on an older ride IMO.

    • Like 2

  14. There's a reason why you don't see KX420s at the vintage races. The KX420 was an absolutely attrocious pile of dog squeeze. The suspension was one step above a screen door closer, the handling was as bad as (if not worse than) the TM400, and the engine made no power above the mediocre low-end hit. And I doubt you'll have much luck finding many parts. I would steer clear of the bike.

    you forgot to mention broken frames...I've seen two with the whole front end snapped off in races, LOL...I stayed away from kawasaki for a while back then.


  15. I've owned both at the same time.. a modded KX250 with flywheel, revalved and resprung suspension, grunt pipe, etc... and a kdx with rev pipe, reeds and a modern USD front end. For me the old style ergos, wide seat, wide ratio, makes the KDX the one I usually want to ride - but I ride mostly single track. I'm thinning my herd right now, and just sold my 07 WR250F, because I ended up riding the KDX much more often and couldn't justify keeping the WR.

    BTW, a properly setup USD front end turns a good KDX into a great bike - it adds a whole new dimension if done right.


  16. compression is about 165, the gear selector shifts through all the gears, the bike does kick over with the clutches in but it won't go into neutral with them in. If i put the bike in 5th gear it kicks over without moving the bike too much (obviously with the clutch pulled in), the idler gear and all the bearings are intact, right side case is perfect, no cracks. Even if it is the transmision, it should still start right? If it has compression, fuel, air and spark... I'm no superstar mechanic... But that makes boom right?

    Not if the timing is off - could the flywheel be out of position? But before you check the flywheel, pull the plug and just squirt some fuel directly into the cylinder, replace the plug (with a new one or one you know is good -sometimes a bad plug will fire outside the cyl, but not under compression) and see if it at least farts - if so, the timing is probably OK, if not, check the flywheel.


  17. Length has a huge effect too. I don't know details, but KX forks are longer than KDX forks so you have to adjust. If you get those KX forks apart might want to consider limiting spacers to keep the geometry of the KDX chassis.

    What works great for that is fatbar adapters. Protapers will then clear the elevated longer forks nicely, and, IMO, the slightly higher bar position is an improvement over stock for most people - it eliminates that cramped up feeling the KDX has compared to later model bikes. The bike I had before this one had shortened KX forks, and they just don't work as well as the full length units. Even elevated in the triples, my current forks get about 11.5 inches of full travel without the tire hitting the fender - they work really well - like they were factory made for the bike. :smirk:


  18. 200 or 220 with modern forks will yield a bike that is competitive in HS. I prefer my KDX over my other two dirt bikes for anything remotely tight - if you do a USD conversion, take the time to set up the USD suspension right though, it will be worth it. I've done two fork conversions, and noticed the triple clamp choice is critical for handling in that you want the handlebar mounts as far forward as you can get them - it makes a huge difference in control and handling. My current KDX uses 03 YZ125 forks with 04 WR250F triples.


  19. i frickin love my 98 kdx 220,sold my crf250x to to buy it and honestly i have way more fun on the kdx,

    LOL, me too! I rode a CRF250x (modded up) for two years, got really bored with riding and quit for a year. :smirk: One night it dawned on me that the KDX's I rode were always fun and could go well on trails the X wasn't much fun on, so I bought a KDX and have been riding weekly since - and that was years ago.

    • Like 1

  20. LOL, then you're not getting up forward enough....

    I'm talking off-idle torque...first and second gear trails where you sometimes need to back off to get around an obstacle, then hit it hard to get up a steep rise - no room to get momentum - that's where the E model 200 and the 220 are better suited than the H 200 - Don't get me wrong, for most things I like the H 200 better, but when things are slow and really nasty - the clutch usually pays the price. A properly setup 220 will stay on the pipe more like a 250, where the 200's will fade out once they start to slow - different porting/kips and smaller carb do make for a better low end bike. I've had a few KDX's, this one is the seventh over 30 years or so - I still haven't found a better all around trail bike. The last 220 I had was a torque monster, with head mods, pipe and reeds, I ended up putting a flywheel weight on it because it spun too easily right off idle if traction wasn't good. :smirk:


  21. When I bought my first H model back in '95 I had a pretty challenging loop set up with some tough near vertical hill trails. I had been riding an 89 E model that I had bought new and was running the stock pipe. Even with an FMF pipe and aftermarket reeds the H model had less grunt for those hilly areas - I was very disappointed. I ended up getting a KDX220 and modified it with pipe and reeds to do the job for that kind of terrain.

    However, the H model has a tighter-feeling perimeter frame chassis, IMO, and can be modified with USD's to be a better all-around handling bike. That's what I'm running now (a 1997 KDX200 with modified YZ125 forks). I'm kinda in the market now for an E model to see what it can do with some modern USD's - then I'll give the final verdict...LOL..no matter what, these bikes are fun.

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