How often should I bleed my brakes?
When you suspect air may be present in your brake system and your brake lever starts to feel spongy, it is time to bleed your brakes.
Many riders will only ever bleed their brakes when trapped air is affecting their braking, but since water content can also have on your brakes perhaps more routine brake fluid changes are in order.
Riders who race and demand the most from their brakes may consider changing their brake fluid annually. For the rest of us changing the brake fluid every two years to maintain a high boiling point is recommended, especially in those brakes which use DOT brake fluid.