Rob Kardashian and Rihanna’s recent trip to the go-kart track was apparently just as innocuous as one would assume a go-karting trip would be.

Rumors swirled when the duo were spotted having a fun-filled night together over the weekend, first hitting Racer’s Edge Indoor Karting in Burbank, California and later Playhouse nightclub in Hollywood. But according to the reality star himself, the only reason he and RiRi were spotted out together is because the two friends were celebrating a mutual pal’s birthday.

“It’s because Rihanna’s a friend, and she is friends with my friend Capricorn, and it was Cap’s birthday,” Rob explained to Ryan Seacrest on KIIS-FM radio this morning. “We all went out to celebrate our friend’s birthday. It was fun. It was a good night.”

With five sisters, Rob probably isn’t in need of another lady friend. But hey, it probably doesn’t hurt to have Rihanna in your entourage!

“Rob’s like a big brother to her and she likes chilling and doing stupid and goofy things with him,” a source told Hollywood Life of the duo’s friendship. “They did go get dinner that night and went to Playhouse... It was a chill night with Rob. Just low-key and Ri said they talked about life and his relationship.”

And as for Rob’s other rumored girlfriend, British singer Rita Ora? Well, the reality star was predictably vague about that.

"I'm just a fan. That's all. I'm a big fan," Rob told Ryan before quickly changing the subject. "I wish you could buy U.K. albums here."

You can listen to his full interview below.

Credit: RyanSeacrest.com Photo: Rob Kardashian Talks Family Therapy, Rihanna Dating Rumors, and Rita Ora with Ryan Seacrest

Source: On Air with Ryan Seacrest, Hollywood Life

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