DS625X Valve Clearance Specification

The official documents give different clearance values and different inspection intervals. This page shows every published value with its document and page. We cannot verify which is correct.

The KEL600 is an inline twin with 8 valves and double overhead camshafts Owner's manual p. 87. The valves are worked by swinging arms, and clearance is set with adjustment shims under the arms Engine manual p. 24. Too tight, and a valve stops sealing fully and can burn. Too loose, and the valvetrain gets noisy.

The engine manual marks valve clearance as a job that needs special tools, data or skill and should be done by a Loncin dealer Engine manual p. 21.

Specifications

Sources: Owner's manual p. 87 and Engine manual p. 10 for the first row; Hungarian owner's manual p. 101 for the second. We cannot verify which is correct. The Hungarian figures are the same numbers the DS525X owner's manual gives for the DS525X (0.16 ± 0.03 mm intake, 0.27 ± 0.03 mm exhaust, Owner's manual p. 87).

Shims come in 89 thicknesses from 1.72 to 2.60 mm in 0.01 mm steps Engine manual p. 27.

On the English owner's manual and engine manual figures, the KEL600 clearances are smaller than the DS525X's on both intake and exhaust.

Inspection schedule

The documents give different intervals. We cannot verify which is correct.

• English owner's manual: inspect at 19,000 km and 37,000 km, which is every 18,000 km Owner's manual p. 89.
• KEL600 engine workshop manual: inspect every 42,000 km Engine manual p. 21.
• Hungarian owner's manual (machine translated): check every 20,000 km Hungarian owner's manual p. 101.
• Swedish owner's manual: gives the service intervals (1,000 km or 3 months, then every 10,000 km or 12 months) but no per-item list, so it does not say at which service the valves are checked Swedish owner's manual p. 84.

Have the clearances checked earlier than the schedule if you notice:

• A persistent ticking or clattering from the top end that varies with rpm
• Hard starting or rough idle that doesn't trace to fuel, ignition, or air filter
• Low compression. The engine manual gives at least 1,200 kPa cylinder pressure when cranking on the electric starter Engine manual p. 10
• Loss of top-end power that you used to have

How clearance is checked

Workshops follow this process. It's here so you understand what they do, not as a DIY procedure. The steps are from the engine manual Engine manual p. 23-24:

1. Engine cold, below 35 °C.
2. Remove the cylinder head cover and its seal ring, and the view-hole cap and its o-ring.
3. Turn the crankshaft clockwise until the base circles of the left cylinder's intake and exhaust cams face the swinging arms.
4. Measure the four valves of the left cylinder with a feeler gauge between the cam base circle and the swinging arm.
5. Keep turning the crankshaft clockwise until the base circles of the right cylinder's cams face the swinging arms, and measure its four valves.
6. Record every clearance. The readings are used to choose the new shims.

Why this is a dealer/workshop job

Measurement is straightforward. Adjustment, per the engine manual Engine manual p. 24-29, requires:

• Setting the timing: the T1 mark on the primary drive gear aligned with the groove on the right crankcase cover, with the "IN" and "EX" marks on the timing driven gears level with the cylinder head surface.
• Retracting and holding the cam-chain tensioner with a special tool, then removing the camshaft bracket (bolts loosened in the order 12 to 1) and the camshafts.
• Opening the swinging arm and lifting the shim out with tweezers or a magnet, with every shim marked so none drops into the crankcase or a spark plug hole.
• A shim kit of 89 sizes from 1.72 to 2.60 mm. The new shim thickness is A = (B - C) + D, where B is the measured clearance, C is the midpoint of the specified range and D is the thickness of the removed shim. Because the documents give different specified ranges, they also give different values for C.
• Reassembly torques: camshaft bracket bolts in the order 1 to 12, in two stages of 5 N·m then 12 N·m Engine manual p. 27; a new tensioner gasket, tensioner mounting bolt 11 N·m and tail bolt 8 N·m; view-hole cap with a new o-ring at 12 N·m Engine manual p. 29; cylinder head cover bolts 11 N·m Engine manual p. 15.
• Turning the crankshaft at least two turns after reassembly and measuring the clearances again.

If the clearances are within spec, no shims are needed.

Owner pre-check before booking

To save dealer time and your bill:

1. Note any abnormal top-end noise (record a phone video at idle, off the centre stand, mic close to the cam cover).
2. Note any rough idle or hard starting and what conditions trigger it.
3. Have the bike's service history ready. They'll want to know the last valve inspection mileage.
4. Ask whether they'll report measurements so the values go on file. This lets you (and any future workshop) track drift over time.
5. Ask which clearance specification they work to, given the different values above.

Power variants

The DS625X owner's manual lists two outputs: 47 kW (63 hp) at 9,000 rpm with 57 N·m at 6,500 rpm, and 35 kW at 10,000 rpm with 47 N·m at 6,500 rpm Owner's manual p. 87. The engine manual lists 45 kW at 9,000 rpm and 55 N·m at 6,500 rpm Engine manual p. 7. We cannot verify which figures are correct. None of the documents gives a separate valve clearance for either output.

Common misconceptions

• "Modern engines never need valve adjustment." Every maintenance table that lists valve clearance includes an inspection (see the schedule above).
• "If I can hear the valves, they need adjusting." Audible ticking usually means clearances are too wide. Tight valves are the dangerous failure mode and they're silent.
• "I can do this with feeler gauges and YouTube." Measurement, yes. Adjustment without shim stock and the right tools, no.
• "My DS525X-owning friend's clearance numbers are the same." On the English owner's manual and engine manual figures they are not. The Hungarian DS625X manual prints the DS525X numbers, which is part of the difference above.

Cross-reference

The DS625X values are cited under Specifications and Inspection schedule above, and the DS525X clearances under Specifications. The DS525X inspection mileage is from the DS525X owner's manual p. 89.

Don't use one engine's values on the other.

Sources

• Voge DS625X Owner's Manual (English)
• KEL600 Engine Service Manual
• Voge DS625X Owner's Manual (Hungarian), machine translated
• Voge DS625X Owner's Manual (Swedish)

Have a logged measurement from your bike at a known mileage? Send it in. We're building a long-term clearance-drift dataset for the KEL600.