Dating back to 1925, the track has changed its configuration and length plenty of times. In 1992, it was at Assen that Mick Doohan's right leg risked being amputated after he fell during a qualification lap and got trapped under his Honda.
His limb was saved by Dr. Costa, but when he came back to win, credit went in large part to the thumb master cylinder Brembo engineers designed especially for him so he could activate the rear brake without using a pedal.
Even though it has 18 corners, TT Circuit Assen is very drivable with lots of fast turns and only one that is tight. This track also stands out because the deceleration is lower than at others. The maximum speed doesn't go over 193 mph but the number of fast curves guarantees the braking systems can cool down with ease.
There are very few problems at this track, but one involves weather conditions. In 2014, the MotoGP riders started off with steel brakes because of the rain, then halfway through the race the rain stopped and many changed to bikes with carbon brakes. But these brakes hadn't been warmed up enough and some of the riders complained about problems in the first few braking sections.
According to Brembo technicians, who assist 100% of the 2018 MotoGP pilots, TT Circuit Assen is only slightly demanding on the brakes. On a scale of 1 to 5, it earned a 2 on the difficulty index, a score that surpasses only that of Phillip Island.