2008 Arctic Cat 366 ATV Service Manual, Page 5Get this manual
Break-In Procedure A new ATV and an overhauled ATV engine require "break-in" periodThe first 10 hours (or 200 miles) are most critical to the life of this ATVProper operation during this break-in period will help assure maximum life and performance from the ATVDuring the first 10 hours (or 200 miles) of operation, always use less than 12 throttleVarying the engine RPM during the break-in period allows the components to "load" (aiding the mating process) and then "unload" (allowing components to cool)Although it is essential to place some stress on the engine components during break-in, care should be taken not to overload the engine too oftenDo not pull trailer or carry heavy loads during the 10-hour break-in periodWhen the engine starts, allow it to warm up properlyIdle the engine several minutes until the engine has reached normal operating temperatureDo not idle the engine for excessively long periods of timeDuring the break-in period, maximum of 12 throttle is recommended; however, brief full-throttle accelerations and variations in driving speeds contribute to good engine break-inAfter the completion of the break-in period, the engine oil and oil filter should be changedOther maintenance after break-in should include checking of all prescribed adjustments and tightening of all fasteners