Just bought an 89 KX250....and its rough.

[Enginerd]

Hey guys.

I picked up this 1989 KX250 last night from a neighbor a few blocks away. I always ride my bike near their house when I'm out with my daughter.  One day as I was passing by, I saw the guy just as he was getting out of his truck to go into the house.  I pulled into the driveway and asked about the bike.  I could tell by looking at the bike from the street that it was an 88-89 125 or 250, or a 500.  The rear fender was my clue! 




Once I figured out it was an 89 KX250, I decided to try to buy it to use the 46mm conventional forks on my 95 KX500.  I've always heard they were very good forks.  Its been treated rough by its previous owners, but I'm thinking about trying to get it running and reliable now.  Decisions, decisions!

What do you guys think?

[Foxx4Beaver]

Does'nt look that bad....how's it run with that pipe?...that does'nt look like the correct one for it...it should tuck up under the tank/shroud like the 500....then again,it's got a Zip-Ty look to it,in order to accept a bigger tank.Did it ever have a bigger tank on it?

This is how they came from the factory...notice how it tucks up under the tank nicely

[motopunk]

looks like a good base for rebuild... what pipe is this?? looks similar to the k5-zip-ty-pipes . i think you could use one of these big tanks on it.

 question: why would you change this 43mm ´89 fork against the ´95 usd-fork?? 1. 250 had always softer forksprings than 500.  2.the conventional forks are good, but the usd-forks are much better in performance.  
if you want to use an conventional fork in your k5, look for a "whitepower extreme 50" fork or "marzocci magnum 45".

[1989kawasaki]

The 89 kx250 did have a pipe like that made for it, but I'm not sure If its for a bigger tank

[Enginerd]

....how's it run with that pipe?...that does'nt look like the correct one for it...it should tuck up under the tank/shroud like the 500....then again,it's got a Zip-Ty look to it,in order to accept a bigger tank.Did it ever have a bigger tank on it?

It may run, but I'm not brave enough to try it.  Its so sketchy that running the engine for the first time may be running it for the last time.  It needs several items fixed before I try to start it.  It has compression though.

The pipe looks totally wrong for the bike. I'm sure its meant for another bike, and has just been adapted to this bike.  The pipe is made by PSI.  I dont believe it ever had a larger tank installed.

[Enginerd]

Question: why would you change this 43mm ´89 fork against the ´95 usd-fork?? 1. 250 had always softer forksprings than 500.  2.the conventional forks are good, but the usd-forks are much better in performance.  
If you want to use an conventional fork in your k5, look for a "whitepower extreme 50" fork or "marzocci magnum 45".

I ride only offroad, and I believe conventional forks are a bit smoother and nicer for general offroad riding if you aren't a die-hard racer.

These forks are actually 46m; not 43mm like the 88 KX line used. With the appropriate fork springs installed for my weight (these forks use the same springs as many modern inverted forks, so the selection and prices are good), and a Race Tech gold valve kit, these should be great forks.  I considered adapting a set of 49mm Showa forks from a 1996-98 Suzuki RM, but these 89 KX forks will be a direct bolt-in to the 95 KX5 frame, and the steering stops will work with no issue.

You are right in thinking that the WP Extreme 50 and the Marzocchi Magnum are great forks, but they haven't been used on a production bike in the US in over a decade. And when they were used on production Euro bikes over here, it was only for a few years, so there are really no suspension shops over here that have much experience with them.  Thats a demerit in my eyes. 

[sandblaster]

Your bike is not that bad.... Believe me....
Yep, your bike has the following forks:
CONVENTIONAL -
KX 89 L / KX 89 R -
CHROME OD 46MM -
C/L 36.75" -
BRAKE MOUNT 78MM -
AXLE CLAMP ID'S 22MM
I rode a XR400 several times last summer with conventional forks and for trail riding, no problems.
They were set up for my weight...
You'll be happy once you get them done.

[Motorrad]

like I told 81cr450  when he was here.    89 K5 forks... setup properly... are nicer than most of the upside down rigs I have ridden

[Enginerd]

Your bike is not that bad.... Believe me....

I bet you do see some bikes in pretty sad condition. 

Yep, your bike has the following forks:

CONVENTIONAL -
KX 89 L / KX 89 R -
CHROME OD 46MM -
C/L 36.75" -
BRAKE MOUNT 78MM -
AXLE CLAMP ID'S 22MM

You'll be happy once you get them done.

Cool.  Thanks for the confirmation sir!

[Enginerd]

...89 K5 forks... setup properly... are nicer than most of the upside down rigs I have ridden

NICE!  Thats what I wanted to hear! 

[motopunk]

in europe came the ´89 250 and 500 with the first 41mm usd- fork and the 125 the last year with the 43mm fork. so i thought that the us-models had still the 43mm-convential fork in.

i compared the spare parts-numbers and i must agree...  you should change the forks between the bikes and test if it has the performance that you looking for...  

i can only speak out of my own experiences about the diferent performances of the ´43 convential fork against the 43mm and 46mm usd- forks. in the woods the old forks are not bad, for dual sport and trail riding its a good compromise. for mx-only use are the usd-forks the best performers( and perfekt in muddy conditions. on the usd is nothing under the frontwheel-axle that can stick into the ground and throw you off the bike)

in europe its also hard to find the wp-extreme-forks . it were stock in the ktm -sx-models in the late ´90´s and also available as aftermarket part ...

[The Flyin Hawaiian]

I remember those pipes. Around that time Honda had started using "lowboy" pipes on their CR250s. It was an attempt to get the weight down low. Some aftermarket companies tried making their own versions of a low pipe for bikes that didnt have them from the factory yet and one of them is the pipe on your bike. Ive actualy been keeping an eye out for one of those pipes for a project I had in mind. If you decide to change it I may be interested depending on the condition. The 46mm forks were supposed to be great for offroad. I know a guy that would swap them from bike to bike

[Enginerd]

I remember those pipes. Around that time Honda had started using "lowboy" pipes on their CR250s. It was an attempt to get the weight down low. Some aftermarket companies tried making their own versions of a low pipe for bikes that didnt have them from the factory yet and one of them is the pipe on your bike. Ive actualy been keeping an eye out for one of those pipes for a project I had in mind. If you decide to change it I may be interested depending on the condition.

I have no attachment to this pipe and I'd prefer a standard FMF or PC pipe.  If I come across something else, I'll make sure to check with you about this PSI pipe.

The 46mm forks were supposed to be great for offroad. I know a guy that would swap them from bike to bike.

I hope to find that to be true! 

[Enginerd]

UPDATE: I decided that even if I yank the forks from this bike, I better see if I can get the engine running.  I first checked for spark with a brand new B8ES plug.  It had some spark, but it was so weak that I couldn't see it in bright sunlight. Had to pull the bike into the shade of the garage to see the spark.  I'm guessing thats much weaker than its supposed to be.  

While I pondered what (if anything) to do about the spark, I decided to check the carb out. The intake manifold (Boyesen Rad Valve I think) and the carb and the airbox boot were all fully coated with oil encrusted with sand. To make matters worse, the rubber boot that connects the carb to the Rad Valve was sitting crooked, and the intake side of the carb was barely seated in it. I carefully removed the carb expecting to see it full of sand......but it was clean as a whistle! The intake was also clean inside, as was the inside of the airbox (...although the air filter was covered with a chocolate brown fuzz).  I cleaned the outside of the carb, and then opened it up.  Nice and clean in the float bowl, and the float height was just about perfect.  However the main jet was a 170 and the pilot jet was a 55.  Both sound too rich for a 250 at my 5000 ft elevation (FYI - my 500 has a 162 main and a 52 pilot). The original B8ES plug was very black and covered with oily carbon.  

Only visible problem in the carb is a good bit of wear to the intake side of the slide. Anybody have a #7 or #8 slide (for a PWK) that they'd part with?

[Enginerd]

UPDATE: The bad news...

The radiators are bone dry. There was no apparent leakage around the head gasket, and the plug was oily (not water washed white), so I was pretty sure the water didn't get into the cylinder. I drained the transmission and a 50/50 mix of water and oil came out!     Me thinks she needs the seal between the tranny and water pump replaced.

I let it drain for an hour, and then refilled with clean oil.  I didn't put any water in the radiators since I was only going to start it for 30 seconds.


The Good news.....It runs! 

With a clean carb, and fresh gas, it fired on the 3rd kick and the top end was even pretty quiet! I didn't even slap a new plug in it! LOL

I let it idle for 20-30 seconds, then shut it off.  After cooling for 15 minutes, I took a quick back alley excursion to check the tranny.  All five gears are present and accounted for, and the clutch was even pretty good. I rode the bike very gently, and when I got back to the garage, the cylinder was just warm to the touch.

Things are looking good so far!