Join Date: Aug 2006
Location: Williamsburg, VA
My front ones were at about halflife at 21,000 mi. The rear had more life then that. This is really a question that depends on your own personal brake usage and riding style (e.g. highway vs. stoplights, taking it easy vs. hard brake, use engine braking a lot vs none). My suggestion is to take the time to actually look at your brakes every once and while. The pads have really easy to see wear notches built in. If you're worried about it get some new pads and take them with you, they don't take up too much space.
"Scarlett" RED 650 K6 ~ 48K mi / Offroad Club #14
...with various wallet deflating additions.