Experienced Valve Tweaker Guide


This is the main service cost for the 950/990 bikes. It takes a bit of time to perform, and at dealer hourly rates, it can add up to quite a large piece of change. However, it is not a task that is beyond the capabilities of an experienced "shade tree mechanic." With a few good tools, most folks who normally do their own motorcycle maintenance should be able to perform a better valve clearance check than the average dealer, plus save a load of cash. The reason I say better is because you as a loving owner will always take more care to "get it right" than the average dealer mech (if not, you shouldn't try this). Most of whom spend all day cranking out as many bikes as he/she can in as short amount of time as possible. I usually spend all day and, in addition to meticulously measuring and rechecking every spec, I use the opportunity to go over every nut and bolt on the bike. It's my arse on the line. It's my feet that have to do the walking if the job's not right. It's my skin that is at stake if something goes terribly wrong. That's motivation enough for me.

I do this check every 10k miles (16,093 km) at the same time as the oil change. Everything is open and easily accessible, so it makes sense to combine these tasks. I've found that after the first 20k miles (32,186 km), that the valves don't change much, so the shims and buckets don't need to be R&R'd, which saves a ton of time.

This tome is not designed to be a step by step "How-to" on doing valve checks. I don't describe how-to to use the basic tools, or how-to R&R every fastener/body panel. It is merely a documentation of the things different about the big KTM's procedure. If you've never done a valve check and adjustment on a motorcycle, you should do further research on the basics. The KTM Repair Manual (Shop Manual) is a good place to start and should be a part of any good 950/990 mech's library. You can get a more basic approach in crwmac's how-to in his Beginner's Guide elsewhere in the HOW.

In addition to the normal hand tools and supplies that the average well equipped gear head has in his/her shop, the following are useful, if not essential for this task.


Special Tools:

So, now that we're mentally prepared with the right attitude and have the needed tools close at hand, lets get started:

Remove the skid plate, front fairing, seat, glove box, and fuel tanks and you will see something like this. The red pre-filter is aftermarket.

The red arrows in the image above point to the three fuel tank mounting points. #2 and #3 are in slots to allow for tank expansion. When you re-install the tanks hang the tank from the top mount (#1) and install all of the bolts loosely (just enough to capture the threads. Then tighten them in order #1, #2, #3. Don't force anything. The bolts are soft and will strip if not started properly.

Remove the air box cover and filter and you will see this view of the Ninefiddy's CVRD 43 carbs. Remove the triangle inspection panels from both side of the airbox. Loosen the Boot clamps at each carburetor. Leave the manifold side tight for now. Disconnect the fuel line at the junction 1/2 way down the frame on the left side. Also disconnect anything else that may be attached to the airbox (such as SLS and EPS carp feces) if you have any. Lift the carbs as an assembly out of the box. Lift one carb at a time. Rear then front is the best sequence. You'll need to push the hoses and idle adjustment cable(s) up as you go. If the carbs won't move, loosen the carb to boot clamps some more. There's a ridge on the carb throat that needs to come loose from a groove in the boot. Tie the carbs up out of the way. A bungie over the windscreen usually works. Next loosen the boot clamps at the manifolds and remove the boots. Then lift the box off the manifolds and set aside. Stuff rags in the intakes to keep hard parts from getting inside and FUBARing your engine.

With the carbs and air box removed, your engine bay should look something like this.

Here's what your beloved Lippizaner will look like when stripped for access to do the valve job. It looks like a lot of disassembly (especially to BMW owners, but really isn't any worse than any modern bike with the cylinder heads in the "proper" location (sticking up not out). It takes me ~ 30-45 minutes to get this far. Its a lot easier to access than my CBR1100XX, for instance and about the same as my ST1100 or my son's VF750 Interceptor.

After disconnecting the low voltage wire connector from each coil, remove the sparkplug coils from the sparkplug tubes with a twisting motion. Now is a good time to clean out the inside of the tubes to the sparkplugs. Use compressed air or your favorite non caustic, contact cleaner. They have drain holes in the bottom to the outside.

When you reinstall them, insure they are fully seated down in the tubes. A shot of silicone spray into the sparkplug end and top seal ring will make removal next time a snap. The top seal on the coil will be slightly recessed (about 1/16") when installed properly. You will generally hear 3 distinct "clicks" as you seat them. The third click takes a little more pressure than the first two and is not as obvious the first time you do it. Still, it can be done with hand pressure. By all means, DO NOT use a hammer, or anything else to persuade the coils to seat. They're $84 each, and probably on backorder when you need one. If seated flush or above the tops of the tubes, a very pesky engine miss may occur. This has caused a few folks some time to diagnose, so learn from their mistakes and do the job right.

Remove the 4 bolts (2 on each side) holding the radiator to the frame, and gently pull the radiator forward for enough clearance to access the front valve area. Some folks remove the radiator altogether for more clearance, but it isn't necessary to get the job done. If you're going to torque the head nuts, you will need to remove the radiator. Then remove the oil tank mounting bolts, return oil line, and swing it out of the way.

Remove the oil tank vent hoses (2) from the front valve cover by loosening the hose clamps and carefully removing the hoses. Note: The "L's" into the valve cover are plastic and easily broken. Take your time.

You can unplug the radiator cooling fan for less clutter. Just remember to reconnect it before installing the carbs afterward. A few folks (including some dealers) have forgotten this step.

Once the oil tank vent lines are removed, a 10mm gear wrench makes quick work of removing the valve covers. The covers should come off the cylinder heads with very little trouble. If they stick, a light tap with a plastic mallet will help to loosen them. Be sure the gasket stays attached to the cover, and check it for good condition and full adhesion to the cover. No sealant should be used on the cylinder head mating surface. If it is in good shape and reasonable care is used in handling, you can re-use it many times.

The rear SLS block off plate. I made mine with simple hand tools from some scrap 1/4" aluminum plate that I had laying around in the shop. Cost $0.00. No need for anything fancy here. They can't be seen from the outside.

The front SLS block off plate. Tight, but still reachable without removing anything nearby, once the carbs are removed.

Here's all the room needed to do a simple valve check/adjustment. Note the bottom is pulled away about 3 1/2 inches.

Remove both spark plugs. Here is the sparkplug tool that was included in my owner's tool kit. Later years are said to not include this very useful tool. If you didn't get one, a thin walled 16mm (5/8") deep socket with a short extension will work in this instance.

This is how the KTM tool looks in the sparkplug hole. Keep track of which cylinder the plugs came out of so that you can look at them and evaluate how that cylinder is running. I make notes in my maintenance records for future reference.

To turn the engine over by hand, you first need to remove the plug from the generator case. It takes a 14mm allen wrench, which just so happens to be the same size as the bolt inside that holds the generator rotor to the crankshaft. Don't worry about loosening the rotor bolt. It's torqued to 150 nm and 243 Locktited.

Now 14mm is a rather large allen size. Most auto parts and regular tool shops won't have one, so you may have to order one. Mine cost $27 USD from a tool specialty dealer (Snap-On). It's a good habit to get into always turning these engines in a CCW (counter clockwise) direction. That is the direction the rear wheel (front too usually) turns when the engine is propelling the bike forward. It makes it easier to keep the compression cycles straight in your mind if you follow the direction the running engine rotates. It is also the only way to get the proper measurement of timing chain slack when you do that. I always start my checks on the rear cylinder. The front cylinder's TDC on the compression stroke is 435 degrees of crankshaft rotation CCW from the rear's.

FYI (just incase you mess up and turn the engine while the cams are out): You won't find this in any KTM manual. The LC8 engine's piston rods ride on a common crank journal. The cylinders are positioned 75 degrees apart, with cyl #1 being the front cylinder. The engine runs in a ccw direction (observed from ignition rotor side) and fires as follows:

  1. Slightly before (depending on the ignition advance) TDC on the compression stroke cyl #1 fires.
  2. 285 degrees of crankshaft rotation later cyl #2 fires (during cyl #1's exhaust stroke).
  3. 435 degrees of crankshaft rotation later cyl #1 fires During cyl #2's intake stroke), and the cycle starts again.

Hence the slightly lumpy exhaust note of the LC8's.

Note: The coils actually fire the spark plugs each time the piston comes to TDC, but the engine only fires when there is a compressed fuel/air mixture (ie: every 720 degrees, or every other upstroke of the piston).

Mess the cam installation up by installing one set on the wrong TDC, and you will have a "Big Bang" twin. The cylinders will fire 75 degrees apart, then coast 685 degrees before the next pulse. Ducati actually did this with their 4 cylinder (2 cylinders fired together, 2 more fired 90 degrees later) MotoGP engines for a season. They had trouble keeping parts on the bikes (vibration was loosening all the fasteners) and went to a more conventional firing order for the remaining seasons. I don't think you'd like the results with the KTM, but if you do it please share your experience with the OC.

This bolt on the right side (clutch side) of the engine is removed to access the indent in the crankshaft for the crankshaft locking tool.

As you turn the engine in a CCW direction on the left side, insert a small diameter tool into the crankshaft locking tool hole on the right side (easier than it sounds) to feel the TDC (piston @ Top Dead Center) indent in the crankshaft and help hold the crank in position against the tendency of the valve springs to push the crank past TDC.

This is the official KTM crankshaft locking tool (0113 080802). You can make one with an appropriate sized bolt (8mm dia X 1.25 thread pitch - 80mm long), but this part is pretty inexpensive. A pointed tool like a phillips screwdriver will work in a pinch, but can cause you a lot of extra time if it falls out while the cams are removed. Another case of the right tool making the job easier.

Turn the locking tool in until the pointed end is snug into the recess in the crankshaft. The top will be flush or slightly recessed as shown in this photo.

Here's a close up of what the stop tool looks like when not in the TDC recess.

This is what it looks like when seated properly in the TDC recess of the crankshaft.

Mark the rear cylinder cam gears from the outside on the tooth closest to the cylinder head surface. This makes it easer to replace them properly on reassembly, as the factory "X" marks on the other side of the gears are hard to see. Note: The 990 cam gears are marked on the outside only and with a single "round circle" (no "x") to indicate TDC when aligned with the cylinder head surface.

This is what I use, but any non flaking paint will work as long as it will stick to the oily surface. This product rubs off easily, so take care not to inadvertently remove the marks during handling when the cams are out of the engine.

The other side (engine side) of the rear cylinder intake cam gear has the "X" mark indicating the proper position at TDC of the compression stroke.

And the "+" mark on the rear cylinder exhaust cam gear on the inside.

Here's a photo of the "round circle" mark on the front cylinder intake cam gear. Note that the front cams use the marks on the outside of the gear, whereas the rear used the marks on the inside. There are lots of marks all around the gears. Make sure you use the "X" on the rear and the "circle" on the front. Also make sure the cam lobes are both pointing toward each other for the rear, and away from each other for the front. Things can really get messed up if you don't follow these two rules, and if you don't have the respective piston at TDC on its respective compression stroke (should be taken care of if the locking tool was used).

Here's how the rear cylinder cam lobes should be positioned when the rear cylinder is at TDC. To remove the cams, first remove the spark plug tube from the cam bridge. A pair of flat blade screwdrivers will do the job if you are careful. Be sure not to damage the o-rings that seal the outside of the tube inside the bridge. NOTE: do not remove the cam bridge unless the cams are positioned as shown (without valve spring pressure), or the bridge may break or be damaged.

The following info is old hat to you experienced wrenches, but I'll reiterate it here for the record since it is so critical:

Check the clearance between the cam lobe and the valve bucket when the engine is cold. As things warm up, the clearances tighten up. If you take your measurements when the engine is warm, the resulting cold clearances will be too loose. Record your measurements for later use.

If the clearances are out of spec, remove the 8 bolts holding the cam bridge and remove the bridge. Two of the valve cover bolts can be screwed into two of the diagonal threaded holes in the bridge to ease R&R. Lift the cams straight up so as to not nick a bearing surface. Again, insure the crankshaft is locked securely with the locking bolt. If the crank spins during this critcal time, the least you will have to do is retime your camshafts. Most likely you will snap a cam bridge like a piece of sugar candy. You can't buy them seperately. They only come with a head. ~700 USD each last I checked.

Next remove each valve bucket with a magnet (careful not to drop one of the shims that may be stuck either to the inside of the bucket, or the top of the valve stem). Measure each shim as you remove it and record it with its location. That way if you get the shims mixed up later, you will know by measuring, which is which. It's most reliable to layout a board with markings for the location of each cam part. For instance: Left Intake - Right Intake - Left Exhaust - Right Exhaust. Keep the buckets in order, as it is good practice to match them back up with their respective cam lobes.

I like to do everything on one cylinder head before going on to the next just to mitigate the opportunities for mixing up the parts. It usually saves time in the long run.

Now plug the figures you got for shim thicknesses and clearances into the respective places on Kamanya's spreadsheet. Or use the KTM Valve Clearance Tables to arrive at the proper shim thicknesses required to bring the clearances into spec. KTM shims come in .050mm increments. As you may notice, .050mm is the total range of the spec. Harley Davidson V-Rod shims are the same 10mm diameter and come in .025mm thickness increments. If you're a real stickler for getting just the right clearance (or just cheap), you can mill or lap your shims for the exact clearances. I shoot for the loose end of the spec, because as OHC valves wear, the clearances will decrease (valves sink into the heads). In rare instances carbon can build up on the valve seating surfaces causing clearances to increase. If this happens to you, and you're sure you measured them right last time, you may want to find out what is causing the carbon to build up. Too rich, crappy gas, not enough WFO, etc. Just sayin'.

Clean the shims and inside of the buckets thoroughly (grease or oil will throw off your final measurements). Replace the shims on top of the valve stems in the little recesses and buckets in their proper locations.

While the cams are out, now is a good time to check the head nut torque. Also check to make sure the "Cylinder Head Collar Nut" Tech Bulletin has been done. If not, do it now. It insures that the torque is correctly applied. As I said earlier, you will need to remove the radiator and rotate the oil tank out of the way to get at the front head nuts, but this only takes another 15 minutes or so. The head nuts shown in some of the photos are the old type without washers. I upgraded to the new nuts and washers at a later date.

The new headnut and washer is on the left. Notice the difference in shoulder height and overall length.

Notice that the washer is visible in this instance. Also note that the head stud is recessed slightly compared to the old nut on the right.

If you have a 2003/2004 and have replaced the head nuts, or if you have a 2005 or newer which includes the upgraded nuts from the factory, I recommend that you retorque the heads every time you are required to remove the cams in order to make a shim change. If the shims do not need changing, leave the head nuts alone. The more times you remove the cam bridges unnecessarily, the more chance for an expensive error. However, if you have a 2003/2004 and still have the original nuts, they have a tendency to not stay torqued. so I strongly recommend re-torquing every valve check, this will require removal of the cams even if your valve clearances are in spec. Consider this an incentive to upgrade to the newer nuts.
(Thanks crazybrit)

These are the two inside cylinder head nuts for which the cams must be removed to access.
(photo by uk_mouse)

These are the two external cylinder head nuts on the rear cylinder.

Remove them one at a time and clean the threads and lube with assembly lube. I use a product made especially for the job by ARP, but clean engine oil will work fine for this task. Important thing is NOT to torque dry threads. Don't undo all the nuts at once.  Remove the nuts one at a time.  Lube and torque the first one to 25nm then remove the second (diagonal one) lube and torque to 25nm. Repeat for the remaining nuts.  Then finish up by torquing to 38nm, in the same pattern.  You don't want to loosen all of the nuts at once as you will then most likely have a head gasket leak

One of the outside head nuts on each cylinder is in a recessed area of the head and requires an adapter. The factory lists 600 29 081 000 (~$55) for this job, but the tool shown above, found in the owner's tool kit, does the job equally as well (and you thought that was just a bottle opener. Crafty Austrians). Just make sure that with either tool, that an angle of 90 deg is kept between the adapter and the torque wrench as shown. Otherwise an inaccurate torque reading will result. Rear cylinder shown above.

The recessed nut on the front cylinder. See why the radiator and oil tank must be moved?

A file may need to be used to remove a tiny bit of material from the toolkit adapter, as shown.

Rear cylinder cams are set back into place with the paint marks aligned with the edge of the head (just like they were when removed).

Reinstall the cam bridge, insuring it is flush with the head surface all of the way around. Torque the 8 bolts holding the cam bridge to an initial 10nm using a diagonal pattern. Tighten the 4 larger bolts to 18nm on the second step. NOTE: The 4 smaller bolts remain at 10nm. You can see the o-rings (green) that seal the sparkplug tube.

Now go through and check each clearance with a feeler gauge to make sure they are in spec. If you did everything carefully, they will.

Re insert the sparkplug tube. It pops in with just hand pressure if aligned properly. Don't get it cockeyed.

A laptop computer is real handy to have around the shop nowadays. Here is a clever spreadsheet from Kamanya, one of our talented OC Inmates, that you can use to record your valve clearances and shim sizes as you do them. It will then compute the ideal shim size for you and even give you part numbers. All it needs to do now is order the parts shipped to me and get me a beer.

You can save the finished form as something like ktm_950_valves_62k.xls and you will be able to go back later to see what they were. Very handy when ordering your next set of shims (ie: you have a record of what size shims is in the engine for next time). You can also easily print out a nice clean form for your hard copy file.

It's also handy if you have Internet access in the shop for those times when you need to figure something out. WiFi is a great invention.

Next, remove the cylinder locking tool (or back it out so it doesn't interfere with engine rotation) and rotate the engine CCW 435 deg to TDC on the compression stroke for the front cylinder. Don't worry too much about the number of degrees, just watch the cams and their gears for the lobes to move to the right position and the marks to align. Replace the locking tool. Here's an image of the front cylinder exhaust cam gear and its "circle" mark in the proper position for TDC. Not the big one. The mark you're looking for is that little "punch-like" mark on the tooth itself. Now you are ready to repeat the valve clearance checks for the front cylinder.

The cam lobes on the front cylinder should face away from each other as in this image. Note: The valve cover bolts make great handles for R&R'ing the cam bridges. Now just repeat the measurements, adjustments, and head nut torquinq procedure as you did on the rear cylinder.

If you get the cams mixed up, don't worry, they are marked with their proper positions. ie: EXhaust FRont in this image.

Likewise INtake FRont here. The rear cylinder cams will be marked IN RE and EX RE respectively.

Now remove the locking tool and reinsert the case bolt with a new sealing washer (if needed) and insert the spark plugs. A dab of anti-seize makes removal next time a breeze. The plug in this image is the OEM NGK CR8EK. It's a good plug and I have gotten good service from them, however NGK makes an Iridium tipped plug (CR8EIX) that I've used since the 20k miles service which seems to idle smoother and run crisper throughout the rpm range. Especially the mid range. At ~ $10 USD, it's a no brainer.

Torque each plug to 12nm. Then reassemble everything in the reverse order of disassembly. Take care that the rubber vacuum lines are in good condition and that the rubber carb to manifold boots are not cracked or cut, and insure that they are seated properly so no leaks occur. Don't forget to plug the radiator fan back in.


Magnetic pickup tool. Invaluable for removing the buckets. This one has a very bright LED light in the tip that comes in handy from time to time.

Otoscope. A handy tool for working on small parts and essential for "reading" spark plugs properly. Not really needed here. Just thought I'd throw it in for interest.


KTM Valve Clearance Tables:


Inch/pounds to Newton-meters, multiply by .113
Newton-meters to inch-pounds, divide by .113
Foot-pounds to Newton-meters, divide by .737
Newton-meters to foot-pounds, multiply by .737

Everything else you need to convert:

Disclaimer: The information contained on this page and on this site is condensed from the combined wisdom of the members and contributors of the Orange Crush Forum. The contributions are reprinted here exactly as posted by the contributors. The spelling, syntax, grammar, etc have purposely not been corrected in order to retain its original flavor. The contributors are from throughout the World, and English may very well not be their native language. Don't be an ass and complain about the lexicon. It is mostly subjective, with a little objectivity thrown in for seasoning, based on the experiences of the contributors. Use this info at your own risk. The site owner is not responsible for its accuracy or validity. None of the procedures described should be taken as recommendations by anyone. Take anything you read or hear anywhere, but especially on the World Wide Web with a very large dose of salt. The cognoscente is a skeptic.