Probably will not have an issue with the arbor but there are other issues to consider. Blade tip speed - making sure that the maximum rpm rating of the blade will not be exceeded by saw designed for a smaller blade. You other issue will be the saw will be more under powered with the larger blade. The larger diameter will require more power from the motor to provide the same cutting power at the tooth. Since you are not able to increase the power you will have less power. That's why radial arm saws were often run with the next size smaller blade to give the motor a little more mechanical advantage. Also why dado blade sets are generally smaller diameter since the kerf will be wider requiring more power.
As to damaging your saw, if you over stress the motor you are creating more heat than the motor is designed to remove and heat kills motors