Many people buy new atv's or rebuild there engines. When you have a new engine with no hours on it, you must break it in. Breaking in an engine properly will affect how long your engine will last. If you do it properly, your engine will last longer. I will tell you the procedures of breaking in a 4 stroke engine.

1.When you get the bike, or are done rebuilding, make sure you have the right amount of oil (brand new) in the bike. Make sure your filter is clean also. Install a new spark plug.

2. After that, for the first 10 hours of opperation, do not go past half throttle. Try to go different speeds as much as you can, but do not go past half throttle while riding. If you do, this could harm the engine. When you are riding, try not to put much stress on the engine (ie. climbing hills etc..)

3. After 10 hours of opperation, go 5 more hours, except this time, you can go 3/4 throttle. Do not go over 3/4 throttle. Again, try to vary your speed as much as you can.

4. After you have completed the riding part (15 hours total) adjust the valves.

5. After adjusting the valves, change the oil again to get rid of all the metal particles that are a result of the engine getting seated all together.


To learn how to adjust the valves, refer to this Remember, when adjusting valves and changing oil, always work in a clean environment, you dont want any dirt or dust getting in your brandnew engine.
I hope this has helped you some