The EXC300 does not come with a flywheel weight. The flywheel itself is heavier than the one you will find on the MXC or SX models. You can ad as little or as much weight to a flywheel as you feel works for you....or you can 'shave' a flywheel to remove weight. I rode a 03' 300EXC just last week and I personally feel it would probaly benifit with a bit more flywheel weight, especially for tight woods. Which ever you choose, have it done by a proffesional, flywheels need to balanced.