Jump to content
Sign in to follow this  

Just picked up a KDX...

Recommended Posts

Now the fun begins...

I just picked up a 1990 KDX in pretty good condition. Ill post some pics below. I have a few questions...

The bike fires up first kick and the guy I bought it from hasn't rode it much in the last few years.

So like most 20 year old bikes, it does need some work. The chain and sprockets are toast. I am debating whether to stick with stock gearing or drop the counter shaft down one to 12. As you can see it has the sand tire on the back so I wasn't really able to ride it around much. he gave me a knobbie so I am thinking I may ride it with that for an hour on Friday. It has a non- oring chain on it. I would prefer a o-ring but i am pretty good about keeping my chain lubed and clean so if a non o ring is cheaper and will last just as long with good maintenance then I am okay with going that route.

Also I haven't ordered a manual yet so I don't know a lot of the specs.

The brakes will need to be bled so what fluid should I use? Dot 4?

I want to change the coolant for good measure. What should I use? Can I just just regular automotive coolant from autozone and flush it out really good? It is currently topped off.

I plan on cleaning the air filter and getting a spare. No biggie there.

Fork Seals - he said they were weeping but I haven't seen anything leaking yet so I will keep a close eye. Any brands you recommend?

Brake pads - eventually they will need to be done. Can I go with cheaper tusk pads?

Expansion chamber - its a pro circut pipe, with the stock silencer. I plan on keeping it this way. As you can see its pretty dinged up. I have the stock pipe as well and its in good condition. I would rather keep the pro circut but not sure if I should do the freeze it with water to push them out. Thoughts?

KIPS valve - from what I have read, this needs to be cleaned often. Is there a tutorial on it. I am sure it hasn't been done and I am okay with doing it.

Jetting - I usually ride from sea level - 3k ft. I may go to the high desert this summer which would put me around 6 or 7 - 9k. I will take the carb out this weekend and see what jets it has in there and clean them out. What does everyone recommend for a baseline with a the pipe and that elevation?

As I learn more I will post up.

Pre-mix- its my first 2 stroke. The guy said he was running 32:1. I dont know what oil he was using. I know everyone has their favorite but if you can let me know whats a good place to start with the jetting + mix. it smokes pretty heavy right now.

Tranny fluid - whats the best to use? I think the clutch might be sticking because it hasnt been rode in a long while. The tranny fluid looks bad. I wanna change it asap. I have some Shell Rotella T that I use in the XR. Will this be okay for a few hours on the tranny? Also how much oil?

24411_557623725683_26201335_32551653_7837801_s.jpg

24411_557623091953_26201335_32551570_2371025_s.jpg

24411_557622852433_26201335_32551536_448298_s.jpg

Edited by keithh2oskier
jetting/oil

Share this post


Link to post
Share on other sites

an o-ring chain will last longer. PERIOD. i have had both and the additional 20bucks for the oring is wrth it. i have gotten double the chain life out of an o-ring.

try stock gearing and see if you like it, thats what i start with.if you dont like it, $7-8 for a diffirent front sprocket isnt much.

do NOT use DOT 4 break fluid in that machine! DOT 4 is silicone based ans it will destroy the seals in the breaks. DOT 3 is safe and probably best.

Tusk pads are just fine, their life vs. brand name are nearly equal.

any auto coolant will work fine. just make sure to mix it 50/50 with water.

if you want the pipe new again, their is a place (cant recall the name) that does pipe repair for a flat 60bucks. small dents dont have much effect on preformance, but large dents do.

if it was my bike i would also change the plug, clean the carb, do a compression test, and pull the headpipe and look at the exhaust side of the piston for wear.

Share this post


Link to post
Share on other sites
an o-ring chain will last longer. PERIOD. i have had both and the additional 20bucks for the oring is wrth it. i have gotten double the chain life out of an o-ring.

try stock gearing and see if you like it, thats what i start with.if you dont like it, $7-8 for a diffirent front sprocket isnt much.

do NOT use DOT 4 break fluid in that machine! DOT 4 is silicone based ans it will destroy the seals in the breaks. DOT 3 is safe and probably best.

Tusk pads are just fine, their life vs. brand name are nearly equal.

any auto coolant will work fine. just make sure to mix it 50/50 with water.

if you want the pipe new again, their is a place (cant recall the name) that does pipe repair for a flat 60bucks. small dents dont have much effect on preformance, but large dents do.

if it was my bike i would also change the plug, clean the carb, do a compression test, and pull the headpipe and look at the exhaust side of the piston for wear.

Thanks. Ill pick up Dot 3 and coolant from the autoparts store.

I plan on doing a compression test. Ill try and get a pic of the exhaust side piston for wear.

From what I have read, 110 links is the correct length for the bike correct?

Share this post


Link to post
Share on other sites

The pipe repair place.. http://www.piperepair.com/

I've used DOT 4 brake fluid in my '04 for a year now with no trouble. In fact, just checked my manual, and Kawasaki recomends DOT 3 or DOT 4 fluid. But, you might wait until you get a manual for the older model, things may be different for a '90. Only benefit to DOT 4 fluid anyway, is a higher boil point.

Share this post


Link to post
Share on other sites

I have the original owners manual and was reading it before bed last night and it answered some of my questions.

-It said Dot 3 for brake fluid.

-For tranny it said to use .79 L of 10w30 or 10w40 motor oil.

-Automotive Coolant 50:50 w/ soft or distilled water.

-Spark Plug Gap

-suspension settings

Eventually I will get a shop manual on ebay when I can find a good price on one.

This weekend I plan to change the rear tire back to the knobbie. Flush the coolant & replace. Change the tranny fluid. Clean the air filter. Lube the suspension. And probably clean other misc. things. Overall the bike is pretty clean so it will make it easy to do general work on it. Now I just need time...

Share this post


Link to post
Share on other sites

Good, sounds like you have most of your questions already answered.

On the tranny oil, the Rotella will work just fine. Matter of fact, a lot of guys swear by it. Me and many others use old Type F auto trans fluid as it works great and is cheaper than the motorcycle oils.

As for premix oil I run the factory 32:1 ratio using Castrol oil. It is a little more smokey than my preferred Golden Spectro but the price is right.

Gearing. Definately ride it before making a decision to change it. I ride really tight single track and the stock gearing works perfectly. Also, with stock gearing 1st gear is almost not usable as it is so low. I can't imagine actually making the gearing any steeper than it already is.

Brakes, yep, DOT3 only and I personally would buy something other than Tusk pads. I have read very mixed reviews about their pads.

Expansion chamber. I wouldn't worry about it unless you have dents in the headpipe. If the head pipe is damaged just replace the pipe. Dents in the chamber section itself won't affect power very much if at all. I even read an article recently where they dyno tested various degrees of damage of a 2T chamber and the bike actually made more power with the dents! The stock silencer is as good as any aftermarket version and a lot quieter to boot!

Chain. O-ring's are nice but a '90 KDX was never made to run one. Be careful about chain guide interference if you decide to go with one. BTW, Fredette makes a guide ($40) for the '90 to use with an O-ring chain.

Share this post


Link to post
Share on other sites

Thanks for the info. Rotella t it is!

I have decided to stick with the stock gearing. Also I am going to go with an oring chain. I was thinking of just filing out the stock guide to get enough room to clear the chain. Looking forward to riding this thing!

Share this post


Link to post
Share on other sites

Where can I find a 1990 kdx 200 manual? I have been searching online without much luck in finding a paper copy of the shop manual.

Clymer doesn't look like they make one for the 89-94 generation and I could only find supplemental ones on ebay.

Thanks.

Share this post


Link to post
Share on other sites

http://www.powersportresource.com/

This is where I got my manual. Only $6.95.

Great bikes, everyone always comments on my KDX. True woods kings.

+1 on the ATF for trans fluid. Cant beat $2.00 a bottle:thumbsup:

I would get approved dirt bike coolant. From what I have heard auto coolant can damge the radiators. I use Engine Ice in my bike and have never had any problems.

I use Yamalube for premix........prefer the cheaper price compared to the other premixes and works just as well.

Any water will not work, make sure it is distilled.

Have fun.

Share this post


Link to post
Share on other sites

Check chain guide clearance for the wider ring chains. You may want to look into a T-ring chain, which is supposedly narrower than some other ring chains.

Dot 5 is the silicone based brake fluid, not DOT 4. Go for DOT 4.

Normal automotive coolant is fine. Mix it 50 / 50 with distilled water.

On fork seals, I recommend OEM.

If you have it in your budget, go for EBC or other higher profile name brand.

Unless you have dents close to the cylinder, I wouldn't worry about trying to split the pipe apart with ice. :thumbsup:

What is your current humidity and temperature?? (as far as jetting) For a general answer, check to see what is in there, but try to go from a stock 48 down to a 45. You might benefit from the thicker stock needle. It helped my '94 with an FMF pipe.

32:1 with a quality motorcycle oil will be good.

If it is nasty, run some cheap car oil through it (10w-40). If your budget allows, go for an oil with a motorcycle on the side of it. I have had good success with Bel-ray Gear Saver. It is designed for 2-stroke transmissions.

The stock fork spring rate is butter soft. You might want to get the correct rate springs for your weight, or at least go with some 1995+ KDX springs that are .35 Kg/mm instead of just .30 Kg/mm.

Be sure to disassemble the linkage and swingarm bearings to clean, inspect and grease.

Manual? I like Kawasaki manuals. :ride:

manuals.jpg

Look on eBay for a used one, if you don't want to pay normal price for one from a dealer. You may want to try to haggle with a dealer. Shop cost will allow them some room to come down.

There is no Clymer manual for KDX's made past 1988. The latest manual is 1983 - 1988 KDX200.

There is a 1989 KDX200 manual, as well as a later 1989 - 1994 KDX200 manual. The later manual's part number ends in -02. There were several changes from 1989 - 1990, so I suggest you skip the 1989 only manual. You may have seen a supplement that is for 1990, or the 1990 - 1993 supplement. Buying the base '89 manual and supplement would work, but it is usually easier to just get the later, '89 - '94 manual. Here is more information on my manual page:

http://www.kdxgarage.com/kdxmanualinformation.html

Congratulations on your purchase!

Share this post


Link to post
Share on other sites

Thanks for the help. I used Rotella T 10-40 in the tranny. Same stuff I used for my XR 200. I have some premix Auto Coolant that I plan to use so I figure that should work out. I was able to find a manual for the right price so its on its way. Once I get its a little more cleaned up I will take some pictures.

Also as far as the suspension goes, I am about 145 with all my gear on. I am only 5'3" so I am pretty small. I am not sure how that effects the suspension but i thought I read somewhere that if your over 150 the suspension would be to soft.

As far as the temp. Right now I am in Sacramento which is about 60* this time of year. During the summer it gets into the high 90s/100s... Summer time has low humidity but its been raining off and on so the humidity is higher in the winter.

Also I have another question. I was cleaning the air filter which is in good condition but I noticed it has two small holes drilled in it. They defenatly look like they were there were there from the factory (whoever made the filter) I dont know if it was for a different bike but I have another air filter on the way so I will swap it out when I get a new one. Just wanted to know if anyone has seen something like this.

Share this post


Link to post
Share on other sites

Wow. 145 WITH gear on. The 1995+ springs would still be better. You might actually want to go down one "normal level" on the spring rate. Stock is 4.6 Kg/mm, but 4.4 Kg/mm might be better for you. Measure the sag and see if you are in range first, of course.

See which jets are in the carb now, then worry about adjusting. I am thinking 45 would be a good starting point.

Two holes in the "exposed to the elements" portion? If so, it sounds like the wrong filter. Standard is one hole in the center for the main bolt. At least silicone seal it up for now.

Share this post


Link to post
Share on other sites

Good idea on the silicone. I plan on pulling the carb today so I will check the jetting and clean the jets out. I plan to measure the sag. From my understanding you measure the distance from the rear axle to a spot on the rear fender with the bike on a stand and then do the exact same measurement with me sitting on the bike. Take the difference and it should be like 100mm +-5 or something?

Share this post


Link to post
Share on other sites

As far as the pipe is concerned I'd try the freezing method and you sould get the majority of the dents out. If you want send it to pacific pipe repair, which was mentioned earlier, and have it fixed. For the chain an o-ring will last twice as long as a meticulously maintained normal chain.

Share this post


Link to post
Share on other sites

So I just checked the Sag. It is 88.5 mm.

I took two measurements one with the bike on the stand the other with me on it and took the difference and it came out to 88.5 mm. That means I should decrease the ride height correct?

Share this post


Link to post
Share on other sites

Well I just got a few hours of riding in today on the KDX. I love this bike. So much fun it makes the XR feel like a SLUG. Bike ran strong all day which is a great sign. Only problem I had was my kickstarter fell off somehow. I got a replacement bolt and was able to find it (after about 20 min of retracing my steps. So now I am going to locktite it so it doesnt come off again...

Ill check that article out.

Share this post


Link to post
Share on other sites

Loosen the adjusting nut on the shock preload. If it is going the wrong way, go the other way. :banana:

Ah, the joy of not having to replace a kickstarter after the nut falls off. ATTENTION everyone, Loc-tite yours on, now! :lol:

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×