I just recently purchased a 06 KTM 50 SX for my 7 year old son. Bike is in great condition and looks like it has very few hours on it. However, the front and rear brakes are spongy. When you pull the front brake lever, the lever will go to the bar and you can still roll the wheel with a good push. Any ideas on what is causing this and how to fix. Thanks for the help!