KEL895 Valve Clearance - Inspection & Adjustment (DS900X)

Unresolved cylinder-head bolt torque: The DS900X engine manual gives 5 N·m + 15 N·m + 90° + 90° for the M9 cylinder-head bolts on Engine manual p. 14, but 5 N·m + 10 N·m + 90° + 90° on Engine manual p. 76. We cannot verify which is correct; neither is selected here.

This site calls the DS900X engine the KEL895. The engine workshop manual calls it the KEL900 Engine manual p. 2, type LX286MX Engine manual p. 7.

The engine is a DOHC twin with four valves per cylinder. Clearance is set with adjustment shims ("washers" in the manual) under the valve swinging arms. Checking needs the cylinder head cover off. Adjusting also needs the camshafts out.

The owner's manual maintenance table says to check valve clearance every 20,000 km Owner's manual p. 88. The engine workshop manual lists Inspect at 20,000 km Engine manual p. 20, and the Hungarian service schedule lists Adjust at 20,000 and 42,000 km Hungarian service schedule p. 1. The engine manual's troubleshooting tables list incorrect valve clearance as a cause of a noisy cylinder head Engine manual p. 58 and of low compression Engine manual p. 59.

Specifications

Where the manuals give different values, each value is listed with its sources and the row is marked Sources differ. We cannot verify which value is correct.

The manual says to check and adjust the clearance with the engine cold, under 35 °C.

Tools and parts

• T60 spline socket to turn the crankshaft
• Feeler gauge
• Crankshaft positioning pin, fitted into the lowest bolt hole of the water pump cover
• Magnet or tweezers for lifting out shims
• Micrometer for measuring shim thickness
• Torque wrench
• New cylinder head cover gasket and new ignition coil seal rings
• Dow Corning sealant (3-0115) for the cylinder head cover gasket Engine manual p. 17
• New washer for the water pump cover bolt
• MP3 grease for the view hole cap seal ring
• Engine oil for the camshaft journals, cams and cam chain

Procedure - Inspection only

1. Prep

Put the bike on the center stand (technique guide) on level ground. Confirm the engine is under 35 °C.

The manual says the cylinder head cover can be removed with the engine in the frame. Its removal list for the cover starts with the fuel tank and then includes Engine manual p. 60:

• the secondary air plug and the secondary air tube
• the breathing tube
• the fuel evaporation parts (carbon canister and the evaporation control solenoid valve)
• the clutch cable, with its locating plate
• both throttle cables, after loosening their adjusters
• the overflow tube and its rubber plate
• the radiator installation bolt
• the brake tube clips on the frame

Then remove the cylinder head cover bolts and the cover, and the view hole cap with its o-ring Engine manual p. 22.

2. Position the left cylinder

With a T60 spline socket, turn the crankshaft clockwise until the base circles of the intake and exhaust camshafts for the left cylinder line up with the valve swinging arms.

3. Measure the left cylinder

Insert the feeler gauge between the camshaft base circle and the swinging arm, and measure all four valves on the left cylinder. Record each value Engine manual p. 22.

When measuring the exhaust valves, lift the pressure relief valve. The decompressor is on the exhaust camshaft Engine manual p. 66.

Acceptable ranges:

• Inlet: 0.11 - 0.20 mm
• Exhaust: 0.26 - 0.35 mm

4. Position the right cylinder

Keep turning the crankshaft clockwise until the base circles of the intake and exhaust camshafts for the right cylinder line up with the swinging arms.

5. Measure the right cylinder

Measure and record all four right-cylinder valves the same way, lifting the pressure relief valve for the exhausts. For the right cylinder the manual's wording places the feeler gauge "between journal of camshaft ... and tappet" Engine manual p. 22. The manual says to record every clearance, because you need them to choose shims.

6. Decide

If all 8 valves are within spec, re-assemble per the final assembly section below. If any are out of spec, go on to adjustment.

Procedure - Adjustment (if needed)

1. Lock the crankshaft in the installation position

Turn the crankshaft clockwise until the hole in the crankshaft timing gear lines up with the lowest bolt hole of the water pump cover. At the same time, the scale marks on the end faces of the intake and exhaust camshaft driven sprockets must be parallel to the cylinder head cover mating surface, with the laser-marked numbers upside down. Then insert the positioning pin into the lowest bolt hole of the water pump cover to lock the crankshaft. The manual calls this the "Condition for Installation" Engine manual p. 23.

The camshaft section of the manual also says to make sure piston 1 is at top dead centre of its compression stroke before removing the camshafts Engine manual p. 61.

2. Release the tensioner

Remove the covering plate of the cam chain tensioner, then remove the hydraulic tensioner Engine manual p. 24.

3. Remove the upper chain guide

Remove the bolts and the upper chain guiding plate. Don't let the bolts drop into the crankcase.

4. Remove the camshaft bracket and camshafts

Loosen the camshaft bracket bolts alternately, working inwards, in 2-3 passes, then remove them. The manual warns that loosening them any other way can damage the bracket, and that the bolts must not drop into the crankcase. Lift off the camshaft bracket with its positioning pins; don't force the pins out of the bracket. Hold the cam chain with a hook, take the chain off the sprockets, then remove the camshafts Engine manual p. 62.

5. Remove the shims

Lift the valve swinging arm and remove the adjustment shim under it with tweezers or a magnet Engine manual p. 63. From the manual:

• Don't let a shim drop into the crankcase or a spark plug hole.
• Mark every shim so it goes back in the right place.
• Measure each removed shim with a micrometer and record the thickness.

6. Calculate the new shim thickness

The manual's formula Engine manual p. 25:

A = (B − C) + D

where:

• A = thickness of the new shim
• B = recorded valve clearance
• C = midpoint of the valve clearance range (0.155 mm inlet, 0.305 mm exhaust, worked out from the ranges above)
• D = thickness of the removed shim

Worked examples (our arithmetic):

Inlet valve, measured clearance 0.30 mm, removed shim 1.80 mm: A = (0.30 − 0.155) + 1.80 = 1.945 mm. The shims come in 0.01 mm steps, so 1.945 mm falls between the 1.94 mm and 1.95 mm sizes.

Exhaust valve, measured clearance 0.20 mm, removed shim 2.10 mm: A = (0.20 − 0.305) + 2.10 = 1.995 mm, between the 1.99 mm and 2.00 mm sizes.

Shims are available from 1.72 mm to 2.60 mm in 0.01 mm steps, 89 sizes.

7. Calculated thickness above 2.60 mm

If the result is more than 2.6 mm because of carbon buildup, the manual says to trim the surface of the valve base Engine manual p. 25. That is machine-shop work. Consult your Voge dealer.

8. Install the new shim

Fit the new shim, taking care not to drop it into the crankcase, then lay the swinging arm back down.

9. Re-assemble the camshafts

From the engine workshop manual p. 65-66:

• When turning the crankshaft, don't press the cam chain into the timing sprocket.
• Turn the crankshaft clockwise and line up the positioning hole on the primary drive gear with the lowest bolt hole of the water pump cover.
• Identify the camshafts: the exhaust camshaft carries the decompressor; the intake camshaft has none.
• Coat the cams, journals and other loaded surfaces with oil, and coat the whole cam chain with oil.
• Fit the chain and sprockets, then the camshafts, with the marks on the driven sprocket end faces parallel to the cylinder head cover mating surface and the laser-marked numbers upside down.

Oil specification: 5W-40, JASO T903 MA2, not oil marked energy saving on the API service label Engine manual p. 8. The API grade differs between documents: "SL or higher" Engine manual p. 26, "SG or higher" Engine manual p. 45 and "5W/40-SN or above" Owner's manual p. 75. We cannot verify which is correct.

Fit the camshaft bracket with its positioning pins lined up with the holes in the cylinder head Engine manual p. 66. Bracket bolts Engine manual p. 64:

• 12 × M7×38 mm bolts, with 4 flat washers Φ7.2 × Φ15 × 2.
• Coat the bolt flange contact surfaces with oil. The torque table also says to coat the thread and base surface with oil Engine manual p. 14.
• Tighten alternately, working outwards, in 2-3 passes. The manual warns that the bracket can be damaged otherwise.
• Torque: 5 N·m + 15 N·m in the torque table Engine manual p. 14; the procedure gives the final 15 N·m Engine manual p. 25.

10. Restore chain tension

Re-fit the upper chain guiding plate, without dropping its bolts into the crankcase. Torque: 10 N·m Engine manual p. 67.

Re-fit the hydraulic chain tensioner and its covering plate. Torque: 15 N·m Engine manual p. 25.

11. Verify

Remove the positioning pin. The manual says to turn the crankshaft clockwise several times, line up the positioning hole on the primary drive gear with the lowest bolt hole of the water pump cover again, check the valve timing once more, and then check the valve clearance Engine manual p. 68. Measure both cylinders again by the inspection method above.

12. Final assembly

• Cylinder head cover: fit a new gasket and new ignition coil seal rings. The manual says to coat the gasket with Dow Corning sealant before fitting it Engine manual p. 61. Cover bolts: 4 × M6, 10 N·m Engine manual p. 14. The torque table note for these bolts says to coat the contact surface of the plate end with oil.
• View hole cap: coat the seal ring with MP3 grease. Torque: 10 N·m Engine manual p. 13.
• Water pump cover bolt: fit a new washer Engine manual p. 25. The torque table lists the water pump cover bolts as M6, 10 N·m Engine manual p. 13.
• Cables: after fitting the cover, the manual says to adjust the throttle cable free play and the clutch lever free play Engine manual p. 61. Clutch lever free play differs between documents: 10 - 20 mm in the engine workshop manual Engine manual p. 10, 10 - 15 mm for the ball joint on the clutch lever in the chassis workshop manual Chassis manual p. 14 and 5 - 8 mm at the lever end in the owner's manual Owner's manual p. 60. We cannot verify which is correct. We have not found a throttle free play value in the manuals.
• Re-fit the parts removed in the prep step, then the fuel tank.

Run the engine briefly and check for oil leaks at the cylinder head cover and view hole cap.

Common pitfalls

• Measuring a warm engine. The manual specifies under 35 °C.
• Skipping the pressure relief valve lift when measuring the exhaust valves.
• Losing track of shim positions. The manual says to mark every shim for correct re-assembly.
• Re-using the cylinder head cover gasket. The manual says to replace it.
• Wrong oil grade. The manual specifies 5W-40, JASO MA2, and says not to use oil marked energy saving on the API service label.

Sources

• Voge DS900X Engine Service Manual (English)
• Voge DS900X Owner's Manual (English)
• Voge DS900X service schedule (Hungarian) p. 1
• DS900X torque specifications: owner's manual chassis torque table only, without the camshaft bracket or cylinder head values.

Performed this on your own DS900X? Send us your notes, especially on the crankshaft positioning pin tooling.

Disclaimer: Valve clearance is engine-critical work. The values and procedure here are from the official engine service manual. If you are not confident with the timing alignment and the camshaft bracket tightening sequence, hand this job to a Voge dealer or an experienced motorcycle technician.