DS800X Rally Engine Oil & Secondary Oil Filter Change

The DS800X Rally uses a wet-sump lubrication system with a single drain plug at the bottom of the case and a secondary oil filter (a spin-on cartridge) that should be replaced at every regular oil change. The full job takes about 45 minutes including warmup and cleanup.

Per the official service schedule, oil + secondary filter is replaced at every service interval - first service at 1,000 km, then every 6,000 km or 12 months, whichever comes first.

Specifications at a glance

Item	Value
Oil grade	SAE 10W-40
API quality	SL or higher - not energy-saving / “Resource Conserving” oils
JASO standard	MA (wet clutch - required)
Oil capacity (drain only)	2.6 L
Oil capacity (drain + secondary filter replaced)	2.8 L
Oil capacity (engine rebuild / dry fill)	3.2 L
Oil drain plug torque	22 N.m (M24 seal plug, replace seal ring)
Secondary oil filter torque	12 N.m (M20)
Oil pressure sensor opening	15-19.6 kPa

The “API SL or higher, not energy-saving” point is non-negotiable on a wet-clutch motorcycle. Energy-saving oils (marked with a green “Resource Conserving” stripe on the API donut) contain friction modifiers that cause clutch slip. JASO MA explicitly excludes those modifiers - buy oil that prints both API SL+ and JASO MA on the bottle.

Note that the DS800X Rally uses 10W-40, not 5W-40 like the DS900X. Different engine, different spec. The KEL800 is happier with the slightly thicker viscosity, especially in warmer climates. If you have leftover 5W-40 from a DS900X service, save it for the next DS900X visit; it’s not a substitute for what the KEL800 wants.

What you need

• 2.6 or 2.8 L of fresh 10W-40 oil (2.8 L if replacing the secondary filter, which you should - a 4 L jug covers it with leftover for top-ups)
• New secondary oil filter (M20 cartridge - Voge OEM or any quality aftermarket equivalent rated for motorcycle use)
• New seal ring for the drain plug (Voge specifies replacement at every change)
• 22 mm or 24 mm socket for the drain plug (depends on production batch - check yours before the job)
• Cap-shaped wrench for the secondary oil filter
• Torque wrench (10-25 N.m range)
• Drain pan (4 L+ capacity)
• Funnel, rags, gloves
• Oil disposal container (do not pour oil down drains - most municipalities have free oil drop-off at recycling centres or auto-parts shops)

Procedure

1. Warm the engine

Ride for 5-10 minutes, or run the engine on the centre stand for 3-5 minutes until it’s at operating temperature. Warm oil drains faster and more completely than cold oil, and carries more contamination out with it. Voge’s procedure is explicit about the warmup duration.

2. Park upright, prepare

Park on level ground with the bike upright (not on the side stand). The KEL800 oil dipstick can give wrong readings if the bike is leaning, so the procedure assumes upright orientation throughout.

Stop the engine. Place the drain pan under the engine.

Remove the oil dipstick / filler cap (this loosens the engine for faster drain - air has to enter as oil leaves).

3. Drain the oil

Locate the seal plug (M24, on the underside of the oil bottom case). Loosen with a 22 mm or 24 mm socket and let the oil drain into the pan. This bolt comes with a sealing ring that should be replaced - keep the old one in case you don’t have a new one on hand, but order a fresh one for the next change.

Wait until the flow has slowed to drips (5-10 minutes). Don’t rush this.

Voge specifies replacing the seal ring when the plug is reinstalled. Don’t reuse - they compress on first use and leak if reused.

4. Replace the secondary oil filter

You should be doing this at every oil change. While the oil is still draining:

• Locate the secondary oil filter on the engine (a small spin-on cartridge, M20 thread).
• Use a cap-shaped oil filter wrench to remove the old filter. It will hold a small amount of oil - direct the open end into the drain pan as you pull it off.
• Inspect the filter mounting surface on the engine - wipe clean with a lint-free rag.
• Take the new filter and coat the rubber o-ring with fresh engine oil. Also coat the threaded portion lightly. This prevents the o-ring from twisting or pinching during installation.
• Hand-thread the new filter onto the engine until the o-ring contacts the engine surface. Then tighten with a torque wrench to 12 N.m.

If you don’t have a torque wrench, the manufacturer rule of thumb after o-ring contact is “3/4 turn by hand” - but a torque wrench is strongly preferred.

5. Reinstall drain plug

Replace the sealing ring on the drain plug. Reinstall:

• Drain plug seal: assemble new seal ring until the plug seals properly, then torque to 22 N.m.

Don’t over-torque. The drain plug threads into aluminium and stripping the threads on the bottom case is an expensive repair (helicoil or thread-sert).

6. Refill

Pour fresh oil into the filler hole using a funnel:

• 2.6 L if you didn’t change the secondary filter
• 2.8 L if you replaced the secondary filter

Pour slowly. The crankcase has internal galleries that take a moment to fill. Don’t trust the dipstick yet - refilling beats dipsticking on a freshly-emptied engine.

7. Check oil level

Critical: Voge’s procedure for accurate dipstick reading on a fresh fill is specific:

1. Start the engine and idle for 3-5 minutes.
2. Stop the engine.
3. Leave the bike to settle for 2-3 minutes (let oil return to the sump from the galleries).
4. Keep the bike upright (not on side stand).
5. Pull the dipstick, wipe with a lint-free rag, insert into oil port without fastening, then pull out and read the level.

The oil level should be between the MIN and MAX marks, ideally near the middle. If below MIN, top up with small increments (50-100 ml) and recheck.

The “insert without fastening” detail is important - the KEL800 dipstick has a screw thread that, if tightened, makes the dipstick go deeper into the case and reads low. The workshop manual says to read with the dipstick simply resting in the hole.

8. Verify no leaks

Run the engine for 2-3 minutes. Stop. Visually inspect the drain plug and secondary filter for weeping. A tiny amount of dampness on a brand-new sealing washer is acceptable; a continuous drip is not.

If anything is leaking, address before riding.

9. Disposal

The drained oil is contaminated and considered hazardous waste. Pour it into a sealable container (the empty 4 L oil jug works) and take it to a free oil-disposal point - most auto-parts shops, recycling centres, and many petrol stations accept used motor oil.

Common pitfalls

• Wrong oil grade. API SL+ and JASO MA are both required. Bargain-bin SAE 10W-40 missing JASO MA will cause wet-clutch slip within a few hundred km. The cost difference between correct oil and wrong oil is 5-10 euros - never worth saving on.
• Using DS900X 5W-40 oil in the 800 Rally. Different bike, different engine, different oil grade. The KEL800 manual specifies 10W-40 specifically.
• Reusing the seal ring. It compresses on first installation. Reusing means slow weeping that gets worse over time. Buy a small bag of M24 sealing rings - they’re 1 euro each and last forever in your toolkit.
• Over-torquing the drain plug. The crankcase is aluminium. 22 N.m on the M24 means 22 - not “tight enough.” A click-type torque wrench is the right tool here.
• Reading the dipstick wrong. The “insert without fastening” detail is documented in the workshop manual. Reading screwed-in gives a low reading; reading on the side stand (leaning) gives a high reading. Upright + finger-rest dipstick = correct reading.
• Skipping the secondary filter replacement. It’s small enough that owners sometimes skip it to save the cost of a new filter cartridge. Don’t - the workshop manual specifies replacement at every oil change for a reason. The filter is what catches the metallic debris that comes from normal engine wear.

Service interval reminder

Per the DS800X Rally periodic-maintenance table (also mirrored in the workshop manual):

• First service: 1,000 km
• Subsequent intervals: every 6,000 km or 12 months

Engine oil and the secondary oil filter are listed as R (replace) at every interval. The owner manual stipulates this even for low-mileage bikes - calendar-time matters because oil oxidises on the shelf, and a year-old oil sample shows degraded additive packages even if the bike has only done 1,500 km.

Cross-reference

The KEL800 is a different engine from the DS900X’s KEL895. Don’t substitute specs:

Spec	KEL800 (DS800X Rally)	KEL895 (DS900X)
Oil grade	SL+ 10W-40 JASO MA	SL+ 5W-40 JASO MA2
Oil capacity (with filter)	2.8 L	3.0 L
Drain plug torque	22 N.m (M24 seal plug)	25 N.m (M16 plus 10 N.m M10 oil-tray)
Secondary filter torque	12 N.m (M20)	11 N.m (M18)
Number of drain points	1 (seal plug only)	2 (bottom case + oil tray)

The KEL800 has a simpler single-drain procedure. The KEL895 in the DS900X has a two-stage drain (bottom case + separate oil tray) that this engine doesn’t share.

Sources

• Voge DS800X Rally Engine Service Manual (English) - pages 22-23 cover the oil change and secondary filter procedures and specifications. This guide is condensed and reorganised from those pages.
• Voge DS800X Rally Owner’s Manual - service intervals confirm the 1,000 km / 6,000 km cadence.
• DS800X Rally torque specifications - full torque table for cross-reference.

If you find better tools or have shop notes that improve the procedure (especially around drain plug access and filter wrench compatibility), send them in and we’ll add them.