The bicycle wheels have the same radius $R$, and the distance between the wheel centers is $l=3R$. Two small stones are stuck in the treads of the front and rear tires. At the initial moment, the stone on the rear wheel is in contact with the ground, and the stone on the front wheel is at its foremost position (see the figure).

The bicycle moves in a straight line with speed $v$. The wheels roll without slipping, and the stones do not detach from the tires.

1 Find the maximum $L_\mathrm{max}$ and minimum $L_\mathrm{min}$ distances between the stones during the bicycle's motion.

2 After what minimum time $t$ from the start of motion does the distance between the stones reach its maximum value?