Oil leak on a Honda Africa Twin CRF1100L 2026

Weeping valve-cover gasket (KTM/Husqvarna 790/890)

Diagnosis confirmed: a cover or case gasket is weeping oil (valve cover / rocker cover, ignition cover, clutch cover, pump cover, etc.). These covers close off openings in the engine and are sealed by a gasket (paper, elastomer, O-ring, or gasket sealant depending on the design). With heat, thermal cycling, and age, the gasket hardens, gets crushed, or cracks, and oil starts to weep -- greasy marks on the casing, drips on the ground, a smell of hot oil off the exhaust. If the leak is moderate, it's mostly just messy; if it's significant, it can drop the oil level (worth watching, especially alongside an oil pressure light). The fix: remove the cover in question, thoroughly clean both gasket surfaces, fit a new gasket (or suitable gasket sealant, matching the original design) and torque it back down, following the correct tightening sequence. This is an intermediate-level job, manageable for a methodical home mechanic, though the difficulty depends on how accessible the cover is (some require removing other parts first). Risk level: moderate. Cost-wise: a gasket costs anywhere from a few euros to about thirty, depending on the cover; a tube of gasket sealant, around ten euros. Important: clean the gasket surfaces thoroughly (old gasket residue), follow the torque value and tightening sequence (a cover that's over- or unevenly tightened will leak again or warp), and check the oil level afterward. This tool helps you understand what's going on -- it doesn't replace a certified mechanic.

How to make the repair yourself

🟡 Intermediate level: a few basic tools and a bit of method are all you need. Work with a cold engine, take your time, and don't hesitate to stop the moment you're unsure.

1. 1With the engine cold, pinpoint exactly where the leak is coming from: clean and dry the area, possibly run the engine briefly, and watch where the oil reappears (valve cover, ignition cover, clutch cover, etc.).
2. 2Get the new gasket of the correct part number (or suitable gasket sealant if that's what the original design uses), plus oil for a possible top-up and a cleaner.
3. 3Remove anything in the way if needed (hoses, cables, sometimes a cover), then take out the cover's screws, noting where each one goes (lengths sometimes differ: sketch it or take a photo).
4. 4Remove the cover carefully and take off the old gasket. Catch any oil that runs out depending on the cover.
5. 5Thoroughly clean both gasket surfaces (cover and engine) to remove all traces of the old gasket and sealant, without scratching the surfaces or dropping debris into the engine.
6. 6Fit the new gasket (or a bead of gasket sealant, evenly applied, if that's the intended design), positioned correctly, without pinching or distorting it.
7. 7Refit the cover and tighten the screws gradually, in several passes, following a crossing/star pattern, to the manufacturer's torque spec (overtightening warps the cover and causes it to leak again).
8. 8Refit anything you removed, check and top up the oil level, start the engine, and check for leaks while hot. Recheck after a few rides.