They aren't hard bikes to work on, it just takes a bit more time since you have to remove the gas tanks for almost any sort of maintenance. I check my valves every 10k miles, but the 990's have a 15 or 20k interval.
"All that is gold does not glitter,
Not all those who wander are lost;
The old that is strong does not wither,
Deep roots are not reached by the frost."
'12 690 Enduro
// 690 Wiki