KDXRIDER.NET

It needs a little love, but whoever put this together did a GREAT job. lots of goodies, like fredette chain guide, O ring chain, FMF pipe, powdercoated engine, skid pan, RAD valve, wiseco clutch basket.... kinda stoked on this one.

I almost didn't recognize the motor!.. What's going on with that radiator #2 return hose on the left side? It's going over the to the right side. it should connect to the coolant exit nozzle on top


I think it was modded to have only 1 rad by the looks of it...But that return hose is mostly gravity fed I would assume. Would leave me questioning how effective the work around is. That little water pump has to push coolant all the way back up to the top of the rad.


cool find !

89 kx125 chassis only had one radiator. What else do you suggest?

Probably works fine...I bet it rips!

Cleaning her up, hanging out with the dog. He's been hunting rabbits all day. Bad day for the rabbits.

learned that that 89year kx 125 forks are the same as a kx500 with different spring rates. also supposed to be rather nice even in kx125 form. 46mm! overhang is massive. someone LAZY took the upper triple off and powedercoated it some god aweful teal sparkly color. even the nice moose barkbusters. ughhhh! rear shock has a (aftermarket) red 5.5kg spring on it it says dsp 5.5 and the shock portion is blown. it looks like the preload is all the way maxed high with lowering links? not sure if the lower links are stock....they look like aftermarket. maybe someone can comment on the specifically 89 kx 125 rear shock? it looks VERY similar to kdx200E. is a 5.5kg not stock? I've been all over the net and not much.

19" rear wheel suprised me, figured it was 18". not sure if this is good or bad. hoops are straight and spokes are now tuned to a high G note. tires are michelin. gearing is 12-45. air filter was a newish moose, so thats good to see. carb is a keihin 39mm!!!!! engine looks awesome all cleaned up.

You're right about that color!

Most MX bikes seem to have 19" rear, and woods bikes have 18's.

12/45 is an odd way to gear it, most would go 13/47 (which is the same gearing ratio). I run 12/48

39mm carb, let us know how the power feels, never heard of a 39mm, might be the kx carb?

so, this thing is running a 39mm airstriker carb(divider plate in carb) with the kx125 airbox. The kx 125 airbox has these dooly-yo's on each side to open it up. hmmm..tune for higher elevation? The compression test, reeds, Kips, and the clutch is tight, changed the oil and plug, and let her rip in the backyard. WOW! not sure if it's the chassis, weight or what but it really rips! lighter than the kdx for sure. wheelies totally possible in 4th. I changed the nasty oil out of the front end. whatever springs are in this thing feel fairly beefcake, yet nimble. I bet I could slam into a 8" log with the front wheel and not feel much.

this is why I even got this bike. I had an ad on craigslist for a WTB extra KDX200E engine. Random dude calls me up, "Hey, I have that, but it comes with this bike". so after messing with this hybrid, which runs GREAT, I tore into this box o' engine that was already mostly blasted apart.

Goods: boysen reed block with branny new reeds. woot!
full set of kips valves and rod in 100% brand new condition
top end thats been worked to high heaven compared to stock. needs re-plate. not sure about it all, but it looks pro.
great crank, with a hot rod crank
stator, both engine cases, clutch cover, transmission, all clips, shim and bearing, stock clutch basket in primo shape with EBC clutch pack and springs, brand new. full cometic gasket kit, a bunch of new in plastic KAWI bearings.... I bet there is close to $500 in new stuff here.

$800 for 89 kx200 done to almost the 9's,with title,and a grip of engine parts. pretty stoked on that.

Cool, how much modification had to be done to the frame? I wanted to do this to a 88 kx parts bike I had but the exaust was to high and would have required cutting the front down tubes to make it work. I wound up using the 1989 kdx frame and used the kx rear sub frame and swing arm on the kdx. Also used a 46mm kayaba front fork off of a 89 kx up front. I haven't finished it yet, I hope it was worth the effort. Thanks for posting those photos

no mods to the frame as far as I can see. I think the upper motor mount is custom and the swingarm portion of the engine case was drilled out. I didn't do the work. the FMF fatty pipe fits perfectly. This thing is a monster, totally different than a kdx. it DOES take more energy to ride than a kdx. I was considering a kx250 just because I wanted some more power than the kdx 200 gave me, but after riding this hybrid, I'll take less weight over more power any day. This swap allows the kdx engine to really shine, I highly recommend a hybrid for the serious rider, it's so worth the effort.

I couldn't take it anymore, I tore the top end off the kx200 today. no kips rattle on idle but the thing runs like a champ. 72mm piston, no KIPS valves in the head...

NEAT hybrid.

What size is that, 240cc??

newbbewb wrote:No KIPS valves in the head...

You're better off. Damn things on the E are a $$ and time consuming letdown

I have not measured the stroke yet, but as far as I've ever read, I would assume 240cc just because it's a 72mm. I don't really know engine dynamics of 2 stroke that well, but the exhaust ports have been modified. When I first got it and took it out with some buddies, I had NO trouble keeping up with the bigger bore bikes, like I said earlier, it really IS a monster. I don't mind KIPS valves too much since I pull the top end down every year anyways. It can be money to fix them though. I really don't know what to think about this bike being a 240cc. I like it I guess? It's nowhere near the power of say a 2004 yz250, but it puts the power down great...it doesn't want to kill you all the time. I can short shift this thing or just let it climb. It has torque everywhere and it has HP at the same time. It gives me gearing options in the tight woods. what I DO like is it still has the KDX thing going on, meaning it will still pull a wheelie out of first at 7 rpms.

I have considered boring my KIPS-snapping E motor to 240cc, but I had heard some folks had trouble jetting them. It sounds as if yours runs great. Good to know.

Was your cylinder bored and plated, or was a sleeve fitted? And this eliminates ALL KIPS machinery, yes? No valves, no bushings, no toothed rod, no twist shaft, no KIPS governor?

I believe it's not plated, but sleeved as far as I can tell. I was "celebrating in the endzone" when I said earlier that the kips was good. the long rod from the outer case still goes up to the head, and the cover and long toothed "actuator" are still on/in the head but is not being moved because the top left handed nut and rod are gone. make sense? I'm going to see what I can do about putting a plug on the lower case and eliminate the whole mess. maybe have my buddy machine a nice aluminum Kips cover without the rod hole. then again if I do that, I can't throw a KIPS enabled head and piston on. I think I know why that rod is still there, so you COULD put a different jug on piston on. I haven't pulled the head to look, why ruin a good thing?

as for the carb, I just pulled it out to clean it up and make sure it was good. It's definately not a KDX carb, wayyy to big. As far as I can tell, it's the factory(hard to find info but think it was a PWK38) thats been treated. I'll worry about it when I have to. it runs PERFECT.

I'm not sure if I would like this engine in my kdxE.

You are able to run the kips valve with that 240 kit. The center valve gets machined down to fit bigger bore. I have KIPS on my 240, while I have not run it with out to see how much the KIPS effects the motor I would bet that it makes a big differance. If it were me I would make it work again.
The availibility of the kips valves are a huge draw back to the e series motor. Used parts are still plentiful though on ebay and CL.

dfeckel,
LA-sleeve does a 240 kit among others, and it is a iron sleeve kit. Wossner makes 3 oversize pistons for the 240 kit so it is serviceable without needing a new liner. Jetting the 240 simply uses standard procedures applicable to any 2 stroke.

My 240 is exactly how you described it. TONS of torque down low almost too much when your tired, keeps up with modern 250f's and 250 2t bikes.
If you have any questions on the 240 kit I am very familiar with them and have been through mine many times.
I would recommend the 240 kit to anyone craving lots of torque down low, and willing to trade some reliability for it.

can't seem to img src google drive pics yet, need to play with it some more...

But here the hybrid stands, cleaned of all the mud I played in. New parts added over the winter, trail tech light switch, TT reg/req, TT HID light, 2 5000mah li-on batteries, head stem bearings, and rear wheel bearings. I also wouldn't mind bending the rear wheel sometime soon so I can get an 18" wheel. I consider this bike done aside from fork upgrades coming in the next couple weeks. These forks are actually great, but that overhang has GOT to go in favor of RM forks.