Other KTM FAQ and Tips

US models..........
EXC-lights,Odo,heavy flywheel,18" rear,large tank,wide ratio gear box, softer suspension, spark arrestor.
MXC-close ratio, heavy flywheel light capable,18" rear,large tank,softer suspension,spark arrestor.
SX- close ratio, small gas tank,19" rear, frequently a year ahead on upgrades compared to the other models,firm suspension.
125-200 share same and motor cases/design.Early years 125EXC.
250-300 share motor and chassis.

96-97- basically the same with the butterscotch orange color and different color graphics. The last years of linkage rear suspension. 125-200(97 only)-250-300-360.

98-99-new bikes with current orange colors, linkless rear suspension, 50mm WP forks. 125-200-250-300-380.

00-01-02-basically the same with upside down 43mm forks. 00 black gas tank,01-02 clear gas tank.125-200-250-300-380.

03-48mm forks and some change in plastics,seat,tank on some models, rear shock has top out spring.125-200-250-300.

04-new one piece rear fender,tank,seat,airbox. 48mm forks,new chassis and motor for 250-300 8lbs lighter, rear has top out spring.125-200-250-300.

05-new mask, no more top out spring in shock.125-200-250-300.

06-new designations, XC replaces MXC, XC-W replaces EXC,no lights or spark arrestors on off road models to help meet US guidelines for 2st imports. These have the lighting coils and lights can be added. Black wheels.
125-200-250-300. EXC kept for 4st bikes.

07-Sx has new body and closed cartridge forks. 450-525EXC are street legal now. 300-250 has elec start as an option.

08-All 08 has new body style. New 4st motor 450-530. 530 has issues with oil transfer, cams or at least start decompress system. I wouldnt buy an 08 450-530.

More later.
"Heim Joint Care
After buying my ktm, read many places that the heim joint needs replacement yearly and not to grease it as it will ruin the "special coating"

I greased it liberally anyway and then took a 3" length of tire tube and put it over the shock end at the lower heim joint and zip tied the top so it wouldnt move. This protects from dirt and water. I powerwash my bike after every ride. After 850 miles on the bike, the joint still looks like new with no play whatsoever.

300/250 power valve pin
Around 06 the 250-300 had a power valve pin that is known to fall out and then the bike runs poorly. It needs to be welded in place. There are exchange services on the net for this.

topic on chain adjustment
KTM's run a looser chain than the typical jap bike. Many ways to do this, follow the manual is one way. The ultimate way to determine where it is ideal is to remove the rear shock and lift the rear wheel til the chain is at its tightest point. Adjust to that point. Put shock back on and then do SOME method that is repeatable to check the chain adjustment. I like to use the top measure method tho. Its easier cuz its on top, why bend way over?? I raise the bike on a stand or lean it over on the side stand til the rear wheel is off the ground. I like to oush down on the chain right at the rear edge of the plastic buffer on the top of the swingarm. The chain should almost hit the metal of the swingarm, but not quite touch.

mounting 2-stroke exhaust properly
I removed my pipe shortly after getting the bike, after re-installing it I had a leak at the cyl. I noticed the pipe was not "square" in the cyl. I used a piece of pipe or wood in the header to bend the header the desired direction and test fit til I got it as close as I could. I added high temp silicone at the cyl, mounted the pipe "loosely" and added the springs to pull it in tight. I then put the bolts in tight and let it sit for 24hrs to dry. No more leaks.

2-stroke pipes
Generally the stoick KTM pipes give the best all around power. They do tend to crack at the seams and mounting tabs in time. They can be welded, but will crack again. The "gnarly" pipe is thicker and less prone to dents and gives more low end for woods riding. BUT you will lose over rev with this pipe.
Things common to the KTM:

Fork seals leak: To fix this get aftermarket seals, I use Synergy brand if I have to change a set. The other thing many guys swear by is cleaning them with the film method. I have done this on my bike, which has stock seals, and it has always stopped the occaisional leak. Have not had to replace these since I got the bike alomost 2yrs ago.

Counter shaft seals leak: Again some guys never have a problem and others cant get it to quit. This system is as follows,from the inside out, a thrust washer,an 0-ring,a sleeve,the outer seal,the sprocket and the clip that holds the sprocket on the shaft. This system relies on pressure from all the parts pushing together to seal the system. Some guys have trouble if they use an aftermarket front sprocket as some are too thin. Most of the time the leak can be fixed by removing the sprocket and sleeve and cleaning the outer seal with a q-tip and the other parts by removing and wiping off. There are new part numbers with thicker o-ring and outer seal starting in 05 that will fit the older bikes as well and fixes most chronic leakers. Often the leak will start after a mud ride or when the bike is left on the side stand for an extended time. Some dont worry about it and call it an auto chain oiler. I have fixed two of the three 200's I have owned and never had to replace the parts again, but have had to clean one, one time. The other cause, and a thing that can break the case, is adjusting the chain too tight.

Rear shock lower heim joint: This is a teflon coated bearing. The manual says not to grease it due to the teflon breaking down from the grease. Belray blue waterproof grease does not seem to hurt the teflon and is used by many to keep this joint from going bad. You can do a quick check to see if it is bad by putting the bike on a center stand and pulling up n down on the rear wheel while watching the lower shock mount for play. Common sense says not to spray this joint directly with a pressure washer. Also a cover of some sort can be used to keep the mud off of it like a piece of inner tube zip tyed on the area.

Rear axle adjuster bolts: The swingarm can fill with water from various reasons. The bolts can and do seize in the aluminum after a few years. To prevent this remove the bolts once a year or so and coat them with an anti-seize compound. The other prevention item is to drill a small hole in the bottom of the swingarm, just in front of the casting, to let the water escape. The right side is more prone to this due to the rear brake guides inserted into the top of the swingarm.

Suspension set-up: The rear on the newer bikes is linkless. In order to have the rising rate effect that the linkage type rear suspension has it must be done thru internal valving. So in order for the valving to be able to do its job you must have the shock shaft in its appropriate place in its length of travel. This is done by having the correct spring for your weight. If the spring is too soft the shock will sag too much and you will be too far into the stroke of the shock to dampen correctly on the small bumps and it will be a harsh ride. If you dont have the right rear spring it will never have the ride it is capable of delivering. The front springs should be matched to the change you do to the rear, but they are more tolerant than the rear.
Bleeding hyd clutch:
They use oil instead of brake fluid until 06. These things are sweet until you get air or the seals leak. They are not hard to work on, but can be difficult to diagnose at first. Use Magura Blood or synth 5w fork oil or synth auto trans fluid.

The #1 thing is air in the system. This can happen cuz you took something apart to work on it,bike was upside down in a crash,or a seal has started leaking. The symptoms will be the clutch suddenly quits working right. The lever is right at the bar and when you put it in gear the lever has no feel and the bike takes off on you. This is low fluid or extreme air in there.

There is a MC rebuild kit avail, but not a slave rebuild. You can however use a new o-ring in the slave and fix most of them. This o-ring isnt avail by KTM for the slave, but there is another one in the motor that is just the right size.The stock size is #0770002210, the larger size is #0770230020. If the bore is scratched or has a shiny spot on it you will need to polish it with 800 grit paper and then put the new o-ring in. Be careful of the spring and ball in there as they may fly out. Put the slave in a clear plastic bag and then pop the piston out by pulling the lever in and it wiil push the piston out. There are several thicknesses of gaskets for the slave so be sure to match it by measuring it.

To bleed you must first have a large syringe like found at a farm or vet supply store. You use it and a piece of tubing that will fit snuggly over the bleed nipple. Take the nipple off and thoroughly clean the dirt out of it or you will push the dirt into the slave and the grit will ruin it. Take off the top cover of the MC and loosen it at the bar to get the resevoir level. If the fluid isnt covering the orofice in there then you have a leak somewhere. It is a sealed system.THE LEVER MUST BE FULLY OUT ALL THE WAY OR IT WONT BLEED. You can loosen the adjusting knob or tie it open somehow if you have problems. If you have bark busters be sure the lever isnt hitting as it may not be fully extended if it does hit.

Loosen the slave bleeder, put the hose on it, and push the fluid up form the bottom. The fluid will go in firmly, but not hard. If its real hard then there is dirt in the bleeder or the lever isnt out all the way. The fluid will overflow and spill on the bike and floor so be sure you have paper down or somehting to catch the mess. Tighten the bleeder. Then work the lever in n out a little and tap on the line in the upper area to try n work out a few more bubbles. You may see very tiny bubbles come out of the MC hole.

If the clutch doesnt work, do it again. Make aure there is no high loop or area where the hose is above the MC. If the clutch works, but fades and then returns later you may have a bad MC. If after a ride or two the clutch goes away again then you need to check the resevoir. If its low again then you have a bad o-ring in the slave. The oil probly wont run out anywhere as it goes into the gearbox along the clutch rod.
125/200 Power valve adjust:
This system is a screw adjustment, no springs like the 250-300.
On the right side of the motor on the clutch case area there is a large aluminum nut. Under this is the adjuster. Remove the large nut, loosen the 8mm head lock nut at the 4 oclock position. There is a large flat sided adjuster under the large alum nut, it should turn by hand. This is what you turn to adjust the power valve opening. It turns about 3 full turns. Do not turn the adjuster to hard once it bottoms out as the balls inside can become stuck if you bottom it hard. Dont loose the large copper sealing washer or the piece of rubber in the lock bolt hole at 4 oclock.

Many will just set it to the "Langston" setting and go. Find that on Transworld MX web site as well as another description of how to do this. Also found there is a part that wears in the system, called the control lever, and will make the bike run real bad like ignition or carb trouble. I chased this for one year before I found it was this part going bad.

The way I do the adjustment is by feel of the "hit". First warm the bike up completely by riding it for 5-10 min. Then remove the parts described above. Turn the adjuster one turn in any direction and then leave the nut cover off and ride the bike. You should be able to feel the difference from where it was set before you changed it if you just rode it for a few minutes like I suggested. As long as there is no water, mud, excessive dust it wont hurt anything to ride it for a minute with the cover off.

Now stop the bike and turn the adjuster one full turn back the other way from where it was originally. Now ride it again and you will have just ridden it with three different settings. This will give you a late opening, an early opening and somewhere in the middle.

Now that you have felt what the adjuster can do go back to whatever opening you liked the best and now adjust it in half turns to fine tune it to where you like it. Some like to just set it to the "Langston" setting and ride. Thats Ok, but I like it a little lower/earlier.

Now to clarify what you are trying to "feel". The hit is just as the bike comes on the pipe, spins the, wheelies or some wording that you will understand. You dont have to ride the bike far to test this, only 100' or so in one gear and feel the hit. Maybe shift gears from 2-3 or 3-4 to feel the hit, not X country riding. Once you have it where you think it should be then put it all back together and then go for a ride to see if it is what you want.
How to fix 125-200 counter shaft seal leaks:
May be same on other 2 strokes also

I just lay it on its side....I did a search on the parts and found that there is a new seal on the 05' that is thicker by .5 mm, #0760324571. Also there are thicker o-rings too, like #0770250020 ...Heres how I do it ,,first I clean the area well so grit doesnt get down inside the hole as you take it apart...take the sprocket off and then clean the splines of the shaft to get more dirt out...I grab the inner sleeve with my fingers and pull it out while twisting. Some might need pliers...the next thing I do is use a seal puller to get the old seal out. It can be done with a screwdeiver, but be careful not to scratch the case side walls when doing this and yes it is in there tight...then reach in with someting with a little hook on the end to get the old o-ring out, a bent paper clip works well...THERE IS ANOTHER FLAT SHIM IN THE BOTTOM. BE SURE IT IS IN THERE TOO...next I inspect the sleeve. If it has grooves deep enuf that you can feel then consider replacing it. If not replacing then use fine sand paper and buff the outside to get it smooth, not enuf to remove the grooves, but enuf to clean it of all tarnish...after this I use the sprocket, and turn it over to the flat side down, as the tool to drive the new seal back in, this way it stays pretty square. Last nite my chain guide got in the way and I used a large socket to finish it up. Just drive it in far enuf so it is flush with the case. It can be pushed in quite a bit further and this is a possibility if you bugger the case or if the sleeve has a groove and you want the seal lips to rub a different part of the sleeve...put the o-ring back in, sleeve in with the groove down and put the spocket on top... The sprocket is also critical in this beacuse it is what puts the load on the sleeve and o-ring to make them seal. If using an aftermarket sprocket it may be a few thousands thinner and then may not be tight enuf...lastly I found that my sprocket clip had grooves worn into one side of it from the countershaft splines. This too will leave a few thousandths of less pressure on the parts. I solved that for now by installing it with the grooves down and fresh metal up. I will have to replace it next time. In order to get the clip in the grooves I use a large socket that just fits over the shaft and give it a few good whacks against the sprocket. If that doesnt do it then use a large tipped, blunt tool to tap the clip around and down, working around the edge until it goes in. The tool must not cut or bend the clip while doing this...thats about it. Some say they try cleaning the seal first with a q-tip and others just replace the o-ring. Others use some various materials under the sprocket to shim a little extra pressure on the seal system and it works for some... You can do any or all of these in steps to save money, but it wont save much time if you have to do it over and over till you get the right combination that stops the leak................
Changing the needle or its setting on a 2st:

remove the top of the carb where the cable goes in. Once this is out the slide is attatched. The needle is hanging down from it. Remove the cable and its spring and guide. You do this by skinning the spring and guide back as far as you can, and then while holding it in your fingers along with the top, you push down on the cable and it slides down and out of its notch. In the bottom of the inside of the slide is a part to remove and the needle is under that. This is a 6mm head, nut device. This is pot metal and will strip if you use a 1/4" socket on it too many times.

The needle has 5 notches in it. Take the clip off the needle and put it back on where you want it to go. Be careful with the clip as it is small and spring loaded. It will fly off and be lost. Put it inside a sandwich bag to remove and re-install it til you are good at doing it. You actually get the clip off by pushing it against a hard surface and it pops off. Put it on in reverse by lining it up and pushing against a hard surface.

Be clear on raising and lowering the needle. To lower the needle to make it a little leaner you raise the clip to the next groove. So lower needle is raise the clip.

When you put the cable back in you need to look at the little plastic part as it has a pin that sticks out to go in the groove to hold the cable in place. Try putting the cable in the groove without the spring first so you can see how it works. Sometimes the spring will slip in your fingers and it can take a few tries to get it done.

When you put the slide back in the carb be sure the needle feeds down into its hole. Twist the throttle a few times and be sure the slide goes up n down freely. If it is hung up and wont drop, it will be stuck wide open. If it is loose then the cable popped out cuz you didnt get it in right.
I am curious about the elec start on the 4 strokes: Do any of you guys use it exclusively or most of the time? If so, how are they for getting a cold or hot one running?
I use mine exclusively. Always starts as long as the battery is good. Battery is always good unless I have not ridden for months. I do use kickstart with elec start if battery is low for first start of day. Hold button down and kick at the same time and it fires in one or two kicks. I have practiced kicking just so I would know the procedure. The RFS motor has firm tension at all times due to valve springs. I relatively slow complete kick thru does the job tho. It is just more resistance than other brands due to the valve springs.
No issues on our electric start KTM's. Hot or cold doesn't matter. As Mikes stated, should the battery be a bit low a couple of kicks and she fires right up.
Electric start will not get you laid. It seems most of you judge a bike on weather or not it has electric start. I can understand why you like the electric start on your four strokes. Because of all the extra moving parts you need to get moving. They Can be difficult to start when hot or cold.
This is my personal opinion ELECTRIC start belongs on street bikes and lawn mowers NOT a dirt bike designed for motocross. If you feel to old or can not get your fat ass up off of the seat. That's when you need electric start and switch to the trails. Because that means you are to old for motocross. So buy an enduro and ride the trails. :smirk: :popcorn:
My Beta actually starts pretty easy with the kickstart. If you drop your bike and it floods, a few seconds on the button can be like fifty kicks as far as getting it going again.

For me the electric start shows it's best advantage when you are in a precarious position and need to start the bike. I have been in that position more times than I can count on my old XR600. It's also nice while on the road and the engine happens to die at a light.
I totally understand why electric start is needed in the trails and or desert riding. I just don't feel electric start needs to be on a bike designed for motocross.
I totally understand why electric start is needed in the trails and or desert riding. I just don't feel electric start needs to be on a bike designed for motocross.

Look at the pros who stall out and have to kick. The 250's seem to be harder than the 450's to start. Which an electric start, hit the switch and your good.
Look at the pros who stall out and have to kick. The 250's seem to be harder than the 450's to start. Which an electric start, hit the switch and your good.
What is the one thing all manufactures tried to do for many years. No matter what type of sport it was. They have always tried to get any bike as light as possible. How much weight do you think electric start will add to the big four Jap bikes?
I can understand having electric start on enduros and street bikes.


Staff member
I totally understand why electric start is needed in the trails and or desert riding. I just don't feel electric start needs to be on a bike designed for motocross.
Just because you don't think electric start belongs on a motocross bike doesn't mean that others don't want it. Don't want it don't buy it.
Electric start will not get you laid. It seems most of you judge a bike on weather or not it has electric start. I can understand why you like the electric start on your four strokes. Because of all the extra moving parts you need to get moving. They Can be difficult to start when hot or cold.
This is my personal opinion ELECTRIC start belongs on street bikes and lawn mowers NOT a dirt bike designed for motocross. If you feel to old or can not get your fat ass up off of the seat. That's when you need electric start and switch to the trails. Because that means you are to old for motocross. So buy an enduro and ride the trails. :smirk: :popcorn:

So only old fat ass people need electric start in your opinion :noidea: