Sounds about right. If you look after them, they can normally go about ten changes. I have 5 on mine atm and at least 5 more unless cracks form like yours did...I have never changed that oil gasket-washer on a Tenere.
However at about 160,000 miles that washer on my Goldwing developed a small crack so I replaced it.
Excellent. Saved ten bucks. Now I can afford to hang with the bimmer boys at Star*ucks twice...
Yamalube is a great insurance as well...LOL, Ron, I hear ya. I've seen crush gasket threads that basically degenerated down to "well, if you don't replace your crush washers every single time you change your oil, then you don't deserve to ride a bike and don't come crying to me if your bike explodes". For years I never changed them, but one of those threads convinced me to change my heretical ways and buy a bag of them. If I remember to dig them out of my motorcycle parts box before I start an oil change, I'll change them, but I still don't end up doing it every time.
I'm baffled sometimes by all the stories of guys stripping out the threads in the sump when they tighten an oil drain bolt. I've never used a torque wrench on a drain bolt, mostly because I'm not sure I'd trust my Pittsburgh torque wrench for it. When I'm tightening anything into aluminum threads, I really err on the side of caution. Basically I go finger tight, then snug up the bolt a little bit, then run the engine for a few minutes. As long as it isn't leaking, I'm good. I've never had one leak over time, and I've never had a drain bolt fall out of the sump, in close to 40 years of riding.