DLE20 Admission valve

This is the admission valve for the DLE 20 single, a small-displacement two-stroke petrol engine for sport-scale models.

The part itself is the admission (reed) valve, which admits the fuel charge into the crankcase and closes to trap it.

Why it is replaced: reed petals lose their spring with age and fail to seal, so the engine idles badly and loses bottom-end power.

Fitting note: Hold the valve up to the light to check it seats, and renew rather than bend a tired petal.