KEL800 Valve Clearance - Inspection & Adjustment (DS800X Rally)

The KEL800 (Loncin engine type LX284MW, Engine manual p. 7) is the 798 cc in-line twin in the DS800X Rally Owner's manual p. 11. Valve clearance is set with adjusting washers (shims) under the swinging arms. Changing a washer means removing the camshaft bracket and camshafts.

The official manuals give different inspection intervals. The owner's manual p. 113 lists valve clearance inspection at 19,000 and 37,000 km. The engine manual maintenance table p. 19 marks it at 30,000 km. We cannot verify which is correct. The Swedish owner's manual has no per-item table Swedish owner's manual p. 120.

The engine manual also gives two different minimum API oil grades for the assembly oil: SG or higher on p. 8 and SL or higher on p. 24. We cannot verify which is correct.

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 engine must be cold, below 35 deg C, for both checking and adjusting.

Tools and parts

• Feeler gauge
• Tweezers and a magnetic bar for removing washers
• Micrometer for measuring washer thickness
• Torque wrench
• New camshaft bracket bolts, washers and seal rings if the bracket comes off
• New seal rings and o-rings for the parts you remove. The engine manual's general rule is to replace washers, o-rings, split pins and locking pieces on reassembly.
• Engine oil for assembly lubrication

Procedure - Inspection

From the engine manual p. 20.

1. Prepare

Park the bike upright on level ground. Confirm the engine is below 35 deg C. Remove the parts that cover the cylinder head cover. Then remove:

• Cylinder head cover kit, the cover and its seal ring
• Left decorative cover, view hole cap and o-ring

2. Measure

Turn the crankshaft counter-clockwise until the base circle of the intake and exhaust camshaft faces the swinging arm of the valve you are checking. Insert the feeler gauge between the protrusion on the swinging arm and the camshaft.

Check every valve on both cylinders. Acceptable ranges:

• Intake: 0.15-0.20 mm
• Exhaust: 0.20-0.25 mm

Record each reading by cylinder and valve. The manual says to keep a record for use when selecting washers.

3. Decide

If every valve is within range, reassemble as described under step 9 of the adjustment procedure. If any valve is out of range, continue with the adjustment.

Procedure - Adjustment

From the engine manual p. 21-22. Notes from the camshaft chapter come from p. 47-53.

1. Set the timing marks

Turn the crankshaft clockwise until the scale line "TL" on the magneto rotor lines up with the timing marks. The mark "IN" on the intake timing driven gear and "EX" on the exhaust timing driven gear line up with the cylinder head surface. "IN" points to the intake side and "EX" points to the exhaust side.

If the marks are not in that position, turn the crankshaft one more round (360 deg) counter-clockwise and align TL with the groove on the left cover. The camshaft chapter describes the TL mark aligned to the gap center of the view hole Engine manual p. 51.

2. Remove the tensioner

Remove the tensioner base tail bolt and its o-ring, the installation bolts on both sides, the tensioner base, the base seal ring and the tensioner. The engine manual covers the tensioner in its camshaft chapter.

3. Remove the camshaft bracket and camshafts

Loosen the camshaft bracket bolts following the reference numbers on the bracket, from 12 to 1. The camshaft chapter says to loosen them from outside to inside, alternately, in several passes, otherwise the bracket can break.

• Do not remove the installation bolt on the camshaft timing driven gear.
• Do not let bolts drop into the crankcase. The positioning pins on the bracket do not need to be removed. Check that the lower seal ring of the bracket is present and replace it if damaged.

Lift off the camshaft bracket and remove the camshafts.

4. Remove the washers

Open the swinging arm and remove its adjusting washer with tweezers or a magnetic bar.

• Do not let a washer drop into the crankcase or a spark plug hole.
• Mark every washer so it goes back in its original position.
• Measure each washer with a micrometer and record the thickness.

5. Calculate the new washer thickness

The engine manual gives this formula:

A = (B - C) + D

• A = thickness of the new washer
• B = recorded valve clearance
• C = given valve clearance
• D = thickness of the removed washer

The manual does not say which point inside the given range to use for C. Washers come in 0.010 mm steps from 1.720 to 2.600 mm.

6. Fit the new washer

• Coat the end of the valve stem with oil.
• Fit the new washer in its original position on the valve spring seat.
• Close the swinging arm.

7. Refit the camshafts and bracket

Coat the camshaft journals with oil and confirm the crankshaft position again. The camshaft chapter says to coat the cams, journals and thrust surfaces with oil. For the oil grade, see the API discrepancy noted at the top of this page.

Hang the timing chain on the timing driven gears and fit the intake and exhaust camshafts. The "IN" mark lines up with the cylinder head surface and faces the intake side. The "EX" mark lines up with the cylinder head surface and faces the exhaust side.

Replace the camshaft bracket bolts, washers and seal rings with new ones. Fit the lower seal ring of the bracket, then the bracket. The copper washers at the four central positions must not be left out.

Coat the thread and seat of each bracket bolt with oil. Tighten the bolts in two stages following the reference numbers on the bracket, from 1 to 12:

• Pre-tighten in several passes to 5 N·m
• Tighten to 15 N·m in the correct sequence

Source: Engine manual p. 52

8. Refit and release the tensioner

Return the tensioner to its initial position, as described in the engine manual's camshaft chapter. Fit the tensioner, the base seal ring and the base, then tighten the base bolts to 11 N·m Engine manual p. 48.

Release the tensioner. Insert a blunt round tool into the tail of the tensioner base and push the tensioner in by 7 mm, then back off. You should feel the tensioner spring forward. The tool must not be sharp and must be at least 7 mm in diameter, otherwise it can damage the one-way valve ball Engine manual p. 48. The engine manual warns that an unreleased tensioner will not work and can damage the engine.

Fit the tail screw with its seal ring and tighten to 16 N·m Engine manual p. 49.

9. Verify and reassemble

Turn the crankshaft two rounds counter-clockwise, then measure the valve clearances again. If any clearance is still wrong, repeat the adjustment.

• Refit the cylinder head cover. Bolt torque 12 N·m, M6, 5 bolts Engine manual p. 13.
• Refit the view hole cap with its seal ring. Torque 7 N·m Engine manual p. 15.
• Refit the left decorative cover with its seal ring. Torque 10 N·m Engine manual p. 22.
• Refit the parts you removed for access.

Common pitfalls

• Measuring on a warm engine. The engine manual requires an engine temperature below 35 deg C.
• Mixing up washer positions. The manual says to mark every washer so it goes back in its original position.
• Ignoring the bracket bolt sequence. The manual gives a numbered loosening and tightening order and warns that the bracket can break if the bolts are not loosened in several passes.
• Leaving the tensioner unreleased. The manual warns this can damage the engine.

Other models

The DS900X uses a different engine (KEL895) with its own clearances and torques. See the KEL895 valve clearance guide and do not use its values on the DS800X Rally.

Sources

• Voge DS800X Rally Engine Service Manual (English)
• Voge DS800X Rally Owner's Manual (English)
• DS800X Rally torque specifications, engine torque table for cross-reference

Performed this on your own DS800X Rally? Send us your notes.

Disclaimer: Valve clearance work affects engine timing. If you are not confident with timing alignment and washer selection, hand this job to a Voge dealer or an experienced motorcycle technician.