Rob Kardashian touts 50-pound

(CNN) — Rob Kardashian not only has a new fiancée, he also has a new body. On Monday, the reality star posted an Instagram photo of himself from when he weighed almost 300 pounds, standing beside Blac Chyna, whom he recently gifted an engagement ring. The caption says, "Looking from where I started 298lbs to my current weight now 248.4lbs. I'm focused and determined to reach my goal weight 200-205lbs .... Happy I found my motivation." Kardashian, who last year was reportedly diagnosed with diabetes, has emerged into the limelight since he has taken up with entrepreneur and model Blac Chyna. The only Kardashian son clearly has found inspiration in his lady love. The pair have posted Snapchat videos showing her yelling at him "Let's go, Robert! I'm not playing with you!" and encouraging him to do sprints. Advertisement Looking from where I started 298lbs to my current weight now 248.4lbs ) I'm focused and determined to reach