The crash happened around 1:45 p.m. Sunday at the 20500 block of SH 36 just north of FM 1462.
Deputies say 80-year-old Charles Raymond Turner attempted to make a sudden U-turn when an oncoming SUV slammed into him.
According to authorities, the impact threw Turner several feet off his bicycle.
After slamming into the 80-year-old cyclist, deputies say the driver of the SUV stopped and called the police.
Deputies say the driver was cooperative, and even offered to submit a blood sample.
State Highway 36 was closed for about three hours during the investigation.
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