MLB Star Yoenis Céspedes -- I'M A CAR PIMP ... Creates 3-Wheeled Monster!!!

NY Mets superstar Yoenis Cespedes channeled his inner Xzibit ... and PIMPED THE HELL out of his new ride -- a custom built 3-wheeled beast that he's now trying to sell.

Cespedes hooked up with Alex Vega from The Auto Firm in Miami to design a 2015 Polaris Slingshot ... which they stripped down to the studs and rebuilt with custom everything.

The end result is pretty cool ... a sick Avorza sound system, crazy lower LED lights that turn the street blue, a turbo kit for extra power and a special Avorza air ride suspension.

We're told Yoenis' MLB contract prevents him from driving the car -- but he loves designing custom rides and figured it would be a fun project.

Now the guys are selling the whip -- asking price is $75k.