Walton, a former pro racer and longtime industry executive, was just transitioning into a new position at Mavic when he suffered a stroke in May this year.
Walton told BRAIN on Thursday that Mavic's parent, Amer Sports, had been "exceedingly generous and patient" during his recovery, but the time came to separate.
"They had to make a move, they need a GM there. ... I respect the fact that they need to terminate my employment; it creates room for right person for them," he said. "I have nothing but good things to say about Mavic and Amer."
A Mavic spokesman said that Larry Burke has moved into an interim general manager role at the company's Haverhill, Massachusetts, headquarters.
"Mavic and Hugh both recognized that his health and full recovery need to be his top priority, and the best thing for him is to dedicate full effort toward rehabilitating," Mavic's Zack Vestal told BRAIN.
Walton underwent open-heart surgery last week to repair damage from a 1999 heart attack. He said there was concern that the surgery, called a Dor procedure, could exacerbate the effects of the stroke, particularly regarding cognition. But he said so far that does not seem to be the case.
Walton said he expects a full recovery but that it will be "many, many months" before he can return to full-time work.
"It's too early to say (when I could return); it depends on my impairment improvements. The impairments I face are that I am easily tired. And I would say my typing. I used to be very good typist. I could crank out large volumes of work. Now that is not possible. I can't type. That is little frustrating," he said.
"I look forward to getting back into the industry that I love, but I can't take on a responsibility that I know in my heart I can't do 100 percent," he said.