HYOSUNG GV125S Owner's Manual page 6

Noise Control System (muffler assembly)
TAMPERING WITH NOISE CONTROL SYSTEM PROHIBITED
Owners are warned that the law may prohibit :
The removal or rendering inoperative by any person
(a)
other than for the purpose of maintenance, repair or
replacement, of any device or element of design
incorporated into any new vehicle for the purpose of
noise control prior to its any sale or delivery to the
ultimate purchaser or while it is in use.
The use of the vehicle after such device or element of
(b)
design has been removed or rendered inoperative
by any person.
MAINTENANCE :
The exhaust system of this motorcycle requires no periodic
maintenance.
The engine should be adjusted to the manufacture's
specifications and the spark plug should be kept in good
condition. Running the engine with incorrectly operating spark
plug or misadjusted fuel injection system may cause permanent
damage to the catalyst and to the noise control system.
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