Elon Musk: Tired but optimistic about Tesla's future

Elon Musk, founder and CEO of Tesla Motors says the electric car company is now building more than 500 Model S vehicles a week and is on target for a major ramp-up in production next year.

"Our big issue is raising production," Musk told CNBC while walking the company's assembly line in Fremont, Calif. "We don't want to be complacent about demand, but our goal is to increase the pace of production. By the end of next year we want to do 40,000 annually."

(Read more: Investors plug back in after Tesla earnings surprise)

To hit that target Tesla will have to boost production by another 35 percent. That's the big question facing Musk and his team at Tesla, as demand for the Model S continues to grow.

On Wednesday, the company said it is now set up to take reservations in China, the world's largest auto market.

Tesla Production

Projected production
2013 21,000
2014 40,000
2016 100,000
Source: Company Estimates

As Tesla ramped up production, Musk spent many long days on the factory floor working with his team as they've wrestled with kinks in the supply chain.

It's one reason why Musk has a desk on the plant floor near the Model S line. "I want to be in the battle, so that means being in the factory I can see how things are going," he said. "It's not the most comfortable place to be, but it's where the action is."

(Read more: Tesla posts surprise profit; shares jump 15%)

It's not a fancy set up. The desk is straight out of Ikea. "I think it's important to be with the team and know what's going on and be able to talk to them. To see what the approach is here and be able to see and solve problems," Musk added.

Musk in for the long run

The incredible success of Tesla over the last year, including a stock price soaring more than 300 percent and the Model S winning a slew of accolades including Motor Trend's Car of the Year and a near perfect score from Consumer Reports, has many praising Musk as one of America's most innovative CEO's.

(Read more: Model S given 5 stars by US safety agency: Tesla)

The rapid growth has also wiped him out.

"I'm often tired," said Musk. "I think I get far too much credit for the success of Tesla. The reason that we've been successful here is because we have a team of some people who work super hard. I'm the one who talks about the results but it's not me who did it really, it's the team here who did it."

Correction: The Tesla Production chart in this story has been revised to show 100,000 for 2016.

—By CNBC's Phil LeBeau. Follow him on Twitter @LeBeauCarNews.

Questions? Comments? BehindTheWheel@cnbc.com.