George Schnakenberg III, 38, of Oakland, was riding a motorized skateboard in a bike lane in the 600 block of Eighth Street around 9 a.m. Tuesday when he suddenly collapsed, San Francisco police spokesman Officer Gordon Shyy said.
Shyy said investigators talked to several witnesses who said Schnakenberg fell while riding and may have hit a parked car after the collapse.
Police said he was taken to San Francisco General Hospital, where he was pronounced dead.
Schnakenberg was the founder and design director of Infinite Collective, an industrial design consultancy firm.
According to the company's website, Schnakenberg started the company in Oakland in 2012 after working in the design industry for the past 15 years.
On his LinkedIn profile, he posted photos of products and projects he has designed, including a coffee brewer, bicycles, skateboards, a 3D-printed keychain and other digital and mechanical items.
He had posted two YouTube videos two years ago of some of his electric bicycle designs.