DIY valve clearance check on a 08/09 KTM 400/450/530 EXC.

[GregMember]

Tools used: spanners/ allen keys/sockets, torque wrench, oil, feeler gauges, calculator, magnet, rags, torch, micrometer, shim kit/access to additional shims

First time this may take you an hour or so, especially if you have to swap shims. After you’ve done it a few times, simple valve checks take about ½ hour or less.

– Clean your bike, having a clean bike is easier to work on and prevents dirt from falling into the engine. It wasn’t perfectly clean here but was clean enough I put it on a scissor lift to make it easier
– Remove the seat via one 8mm fastener located under the rear fender. Pull up hard on the rear of seat to remove it.
– Remove the fuel tank via three 8mm bolts, two in front on the radiator shrouds and one from under the seat. Disconnect the fuel line. Splay the shrouds to the side and lift the tank free.

– Clean the area under the tank to prevent dust from working into the engine.
– Disconnect the crankcase breather tube from the head, you can either do this at the head itself or at the T junction.
– Remove the 4 off 10mm bolts securing the valve cover. Carefully remove the valve cover to the left side. Note: it may be necessary to turn over the engine slightly to remove the cover. To do this: Place the valve cover back into position and turn the engine over slowly with the rear wheel (6th gear). Do not try to turn over the engine with the valve cover partially removed, you could break the cover.

– Rotate the engine to TDC by putting the engine in top gear and turning the rear wheel or sprocket. TDC is where the exhaust lobe faces away and slightly down from the exhaust valves and the intake lobe faces away and slightly down from the intake valves. Both of the rocker arms should have a slight play to them at this position.
– You can use the locking bolt located down below the water pump to determine TDC. To do it this way simply remove the bolt, turn the engine over slowly while looking through the hole with a flashlight. Eventually right after you see the intake valves drop, you will see a notch in the flywheel indicating TDC. Then remove the thick washer and then use the bolt to lock the engine in position. If you don’t need to pull the cams to remove the shims this step really isn’t necessary. I just lined up the mark on the cam with the notch in the head.

Notch in the head

Mark on the cam

– Use a feeler gauge to check the clearance for the between the rocker arm and shim on the two intake valves. Clearance should be 0.10mm-0.15mm. The feeler gauge should have a slight drag when inserting/removing on the correct measurement.

– Use a feeler gauge to check the clearance between the rocker arm and shim on the two exhaust valves. Clearance should be 0.12mm-0.17mm.

– If the clearances are in spec, you are ready to start reinstalling, the valves I checked on Chris’s bike were in spec and all good so I stopped here.

If they aren’t write down the clearances and proceed.

– Now you will remove the rocker arm of the valve that is not in spec. First stuff some rags into the cam chain opening so that nothing falls in the abyss. Then remove the 10mm fasteners on each side of the rocker arm.
– Next remove the cap (8mm hex) on the right side of the head.
-To slide out the rocker arm shaft, gently use a threaded a M6 bolt partially into the shaft and used it to extract it.

NOTE: When removing the exhaust rocker arm shaft you may have this problem where one of the bolts cannot be removed as it hits on the tank mount. This seems to be limited to the 530 models.. Cut approx 5 mm off the tank mount, it isn’t threaded near the tip anyway. Use a spacer when reassembling.
– Now slide the rocker arm out of the way, you will now have access to the shims. Carefully using a magnet remove one of the shims. Don’t remove both at once or you will lose track of which is right and left.
– Using a micrometer or maybe a digital callipers measure the thickness of the shim.
– Then use the following formula to calculate the new shim size.

New Shim Size = Measured Clearance – Desired Clearance + Existing Shim Size

– Install the new shims and measure, calculate and swap the other shim if necessary. Then place the rocker arm back into position, oil the rocker arm shaft and slide into position and reinstall the two bolts and end cap. Torque the two bolts to 15 Nm and the End cap to 10 Nm.
– Repeat the previous steps for the other set of valves/rocker arm if necessary.
– Reinstall the valve cover and torque the four 10mm bolts to 10 Nm.
– Don’t forget to hook up the breather hose.
– If you used the locking bolt in step 9, make sure you remove it and reinstall it with the thick copper washer.
– Double check your work and reinstall the tank (three 8 mm bolts) and seat (8mm bolt). Don’t forget to hook up the fuel line and turn the fuel to on.

The Harley Davidson V-rod and Buell 1125R both use 10mm shims, and since both are considered performance engines, the shims they use are of equal quality to those in your KTM. The shims they sell are available in half sizes which aren’t even available from KTM (i.e. 2.425mm) less than half of what KTM charges which is a surprise eh NOT!

TB

[AlexMember]

Nice one TB. If useful to anyone I use an old sheet cut to size to wrap around the frame/wires/cables to hold everything out of the way and stop dirt from falling into the engine.

[Richard WMember]

Also a good idea to check how much free play is left on the cam chain while your on the job.

[GregMember]

Dickie wrote:

Also a good idea to check how much free play is left on the cam chain while your on the job.

Both great tips there cheers boys

TB

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