Honda CRF250R 2022 Owner's Manual page 65

Exhaust Pipe and Muffler
The exhaust pipe and muffler are stainless steel
but may become stained by mud or dust.
To remove mud or dust, use a wet sponge and
a liquid kitchen abrasive, then rinse well with
clean water. Dry with chamois or a soft towel.
If necessary, remove heat stains by using a
commercially available fine texture compound.
Then, rinse by the same manner as removing
mud or dust.
NOTICE
Even though the exhaust is made of stainless
steel, it can become stained. Remove all marks
and blemishes as soon as they are noticed.
Caring for Your Vehicle
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