While Jesse James was playing the role of dutiful husband to Sandra Bullock, the snake was allegedly carrying on steamy affairs with ELEVEN other women, The ENQUIRER has learned.

Jesse was so brazen, insiders say, that he even had sex trysts in his office while Sandra was at his West Coast Choppers headquarters garage!

A wide-ranging ENQUIRER probe into the tattooed Monster Garage star’s secret double life has also discovered many allegations that he owns Nazi memorabilia and is a raging racist who’s quick to hurl vile ethnic slurs.  The 40-year-old philanderer has battled alcohol problems, served time in a juvenile detention facility and survived a murder attempt by an obsessed female fan.

And in a stunning slap in the face to his movie star wife, sources say Jesse turned his office into a sleazy sex den where he played porn movies and engaged in rough sex with a string of lovers.

"Jesse’s a monster!" declared the insider. "He’s always been the baddest of boys who’s had sexual encounters with random women – and it didn’t stop after he married Sandra."

The hulking biker regularly bedded strippers in his office at his West Coast Choppers building in Long Beach, Calif., according to the source.

"He’s even had sex with other women right under Sandra’s nose! One girl said Jesse would take her into his office and lock the door, while Sandra was in the garage!

"Jesse was also into rough sex. One woman said he’d grab her by the neck, put her up against the wall, and tell her how hot she was."

One gorgeous tattooed blonde – a 32-year-old single mom – thought she was Jesse’s only mistress, until tattooed stripper Michelle "Bombshell" McGee went public with details of her alleged affair with the celebrity mechanic, said an insider close to her.

"He’d call her about once a month, usually around lunchtime, and say, ‘Come over.’ She was so crazy about him that she’d drop everything and run over. She said they’d have wild sex for three or four hours."

A former female employee at West Coast Choppers, Deann McClung even slapped Jesse with a lawsuit in 2000, claiming he brutally forced her into performing oral sex on him in court papers.

"Jesse James is a brutal, terrible person with no heart, no conscience," she said. "He uses people to get what he wants and he throws them away."

After an undisclosed settlement, the lawsuit was dismissed without any confirmation of the allegations.

In another sick twist, The ENQUIRER has discovered Jesse’s Nazi memorabilia that he kept it in his office and the home he shared with Sandra. Jesse also reportedly was photographed wearing Nazi regalia and giving a "Heil Hitler" salute.

"Jesse has a long surfboard with a full-length picture of Adolf Hitler doing the ‘Sieg Heil’ salute, along with a swastika, in his office," explained the insider.

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