ATHENA Timing Chain for HONDA CRF 250 2018-2026

On HONDA CRF 250 from 2018 to 2026, the ATHENA S41400023 timing chain fits in place of the original part. On a four-stroke, the timing chain links the crankshaft to the camshafts. A tired chain gets noisy, upsets the timing and can jump a tooth: with valves hitting the piston, the damage is severe.

Specifications

• Brand: ATHENA
• Manufacturer part number: S41400023
• EAN code: 8050038444347
• Engine: 4-stroke

When to replace it?

• Rattling or chain noise on the timing side, especially at idle.
• Tensioner at the end of its travel.
• Timing marks that no longer line up.

At the intervals in the service manual, and as soon as the tensioner reaches the end of its travel. Check the sprockets and the guides at the same time.

Fitting tips

1. Set the engine at top dead centre on the compression stroke, marks aligned, before removing anything.
2. On most motocross engines the chain is endless, with no master link: replacing it means removing the crankshaft sprocket or a camshaft, as described in the manual.
3. Line the camshafts up with their timing marks again, then put the tensioner back under tension.
4. Turn the engine over two full turns by hand and check the timing again before starting.
5. Refit with a valve cover gasket in good condition.

Why ATHENA?

Founded in 1973 near Vicenza, Athena is an Italian engine gasket specialist that has made its gaskets on its own production lines since day one, as well as a renowned manufacturer of pistons and cylinder kits. The brand supplies original equipment to manufacturers such as KTM, Ducati, Fantic, Piaggio and Triumph, and is a partner of the MXGP motocross world championship.

Spare parts and items to plan

• Cam chain tensioner : GE.CO
• Valve cover gasket : BIHR · ATHENA
• Valve shims : PROX 29.748 · PROX 29.VSA748
• 4-stroke engine oil : LIQUI MOLY 10W40 1 L · MOTUL 10W50

Frequently asked questions

Should I replace the tensioner?
Check it: a worn tensioner, or one at the end of its travel, must be replaced along with the chain.

Compatibility

Check the exact model and year of your bike in the list below before ordering.

Fits:
HONDA CRF 250 2026
HONDA CRF 250 2025
HONDA CRF 250 2024
HONDA CRF 250 2023
HONDA CRF 250 2022
HONDA CRF 250 2021
HONDA CRF 250 2020
HONDA CRF 250 2019
HONDA CRF 250 2018