My 07 WR250F front brake is getting spungy. I can squeeze it hard and it'll travel over an inch and still could not lock up front wheel. Could that be the master cylinder or the caliper? If either could cause the symptom, which part should I start and how to test? It's not air in the system as I can keep pumping the lever and it won't firm up and the action stays the same as described above. Thanks in advance for any input.