James and his girl are on the dirt bike escaping from a car

James and his girl are on the dirt bike escaping from a car load of bad guys.

If we have the following conditions:

James mass is 95 Kg

His Girl is 58Kg

The Dirt Bike’s mass is 115 Kg

The tires on the dirt bike are 0.5m in diameter

With James and the girl on the dirt bike it can reach a top speed of 120 KpH

The coefficient of static friction between the bike and the road is 99.03

The coefficient of kinetic friction between the bike and the road is 8.74

There are 4 bad guys the car each with a mass of 95 Kg

The car is 2.3 m wide and has a mass of 690 Kg

The coefficient of static friction between the car and the road is 99.03

The coefficient of kinetic friction between the car and the road is 8.74

With the 4 bad guys in the car it can reach a top speed of 129 kph.

Each lane of the road is 3.5m wide (so the road is a total of 7m wide)

How fast can the dirt bike go around a 90 curve without losing traction? (show all work)

As they pull out of the curve, and the bad guys start to catch up, the woman pulls a knife and tries to stab James. During the fight he knocks her off the bike and leaves the road heading for a ravine that is 20m across. His path is along level ground and he is traveling at maximum speed. The side of the ravine he starts from is higher than the side upon which he just barely lands safely. If we ignore air resistance, what is the height difference in the sides of the ravine? (show all work)

If the car load of bag guys follow can they also survive the jump across the ravine? (prove your answer)