The first crash happened around 10pm Saturday in the 800 block of Beaumont Highway at Gulf Pump Rd.
Police say the motorcyclist was eastbound on Beaumont Highway when a man driving a pickup truck tried to turn onto the highway from Gulf Pump Rd. The driver failed to yield the right of way and struck the motorcycle.
The man on the bike was airlifted to Memorial Hermann Hospital in serious condition. The driver of the truck was not injured and police say he was not impaired.
The second crash happened around 12:30am Sunday on Beaumont Highway at Redwing.
Deputies say the victim was traveling west at a high rate of speed when he crashed into the back of a slower-moving pickup truck.
The motorcyclist was ejected and landed in a ditch beside the road.
Investigators say he was not wearing a helmet and died on impact. His name has not been released.
No one inside the truck was injured.