I had a '79 CM185T that was nearly indestructible, until I destructed it...
I commuted on it for 15K miles, 60 miles per day at 60mph, getting 65 mpg hauling my 250 lbs with windshield day in and day out. Motor never complained a bit until the countershaft seal backed out at speed and pumped all its oil out on the ground. Seized 'er right up!