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LORDSTOWN, Ohio - Vice President Joe Biden slammed the Republican ticket on Friday, just one day after Mitt Romney officially accepted his party's nomination, saying that much of what they spoke about at the convention "wasn't on the level."

Speaking before a local auto workers union, Biden criticized Ryan for linking President Obama to the closing of a GM plant in Janesville, Wis., Ryan's hometown, but the plant actually stopped producing GM vehicles in 2008 while George W. Bush was still president. Biden didn't mention that the plant completely ceased operations - a small force continued work for Isuzu - in April of 2009, several months after Obama took office.

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"You heard Congressman Ryan on Wednesday night, in a stirring speech, blame the closing of a GM plant in his hometown of Janesville on the president of the United States. Folks, let's look at the facts. The one thing the congressman was right about, and I know from my own community of the two plants closed in Delaware, it was devastating for the people of this community," Biden said at the local UAW 1714.

"But what he didn't tell you is that plant in Janesville actually closed when President Bush was still in office. He didn't tell you that," Biden said. "What they didn't say, but for the sacrifices you all made, and the courage of the president of the United States, all those GM plants would be closed here, across the country."

The plant rolled its last GM SUV out the door in December 2008 and stayed open for a few months in 2009 to complete orders on Isuzu vehicles. The plant then went into standby mode and has remained in that status ever since.

Biden, who was speaking at a union site close to a new GM plant that's set to produce the new Chevy Cruze, pointed to new jobs and investments made in the auto industry here in Lordstown, along with the $23 billion companies like Ford, Chrysler and General Motors have promised to invest in production on American soil.

"What they didn't say at their convention is because of the auto rescue, there are 4,500 of you working here today making a decent wage. What he didn't say, GM is adding two shifts, GM has already announced a $200 million investment here in Lordstown," Biden said. "It's not the Bain way, not in Mexico, not in China, not in Vietnam, but in Lordstown, in Detroit, in Toledo, in Cleveland. Made America, made in America."

Brendan Buck, a spokesman for Ryan, said, "The vice president can't answer for this administration's unfulfilled promises and failed record. The president inherited a troubled economy, but he's not made it better - he's made it worse, with fewer jobs and lower incomes for middle-class families. Like many towns across America, Janesville, Wisconsin, is still waiting for the recovery the president promised."

Biden criticized Romney's position on the auto bailout and lobbed a new Bain attack at Romney, citing a recent piece by Rolling Stone correspondent Tim Dickinson that alleges Romney was, said Biden, "willing to go to extremes to secure a federal bailout" for Bain.

"You know, he's absolutely against the federal government or any government using funds to save jobs and save industries. That's not his view in the free enterprise way. He says it's bad for business, except when it comes to his business," Biden said. "The way Bain Consulting reorganized cost the government and American taxpayers $10 million."

"Now, imagine that. It was one thing when a million middle-class jobs were on the line. It was another thing when his own financial interests and those of his partners are on the line. And now - and now they say they care about the middle class. Isn't it amazing how they found the middle class? They were searching all around, and they found it," Biden said to laughter.

Biden told the crowd he was proud to speak before a group of autoworkers because "as the son of an automobile man, this makes me feel good. My dad sold what you make, and he sold Chevys, by the way."