When breaking in a GO motor or any motor at that, it puts a lot of stress on the conrod and bushing in the con rod because of it being new and the tight pinch. So it's always good practice to change it after break in. It helps the motor stay in it's top running condition. To this point so far, GO is the only manufacture that I'm aware of that provides and additional con rod. Everybody else you have to buy it. One more reason why GO Engines stays ahead of the competition!