Business is booming at OCC, and Paul Senior has hired the young, ambitious Evan as creative director, making him in charge of managing and fabricating new bike builds. Goody's Popcorn commissions a chopper that they intend to raffle off to raise money to send popcorn to military troops. Evan helps Jason design the bike and seems to be taking charge of the build, but when he decides to fabricate a unique glass-sided gas tank using an old-school method, the crew becomes skeptical of Evan's skills. Furthermore, Evan takes it upon himself to deal with the client directly, which is against the rules of OCC. Senior puts Evan on probation, forcing him to take a back seat on the next build so he can focus on learning how OCC operates.

GAF, the largest manufacturer of roofing in North America, approaches Paul Senior about building a bike for them. The only issue is they want it built in time to give it away to a veteran at Sturgis, which is only two and-a-half weeks away. The pressure is on and there's no margin for error. After getting off to a rocky start at OCC, Evan is on probation but is anxious to prove to Paul Senior that he can handle the role of creative director. He convinces a reluctant Paul Senior to give him another shot to run the build. Evan needs everything to go perfectly, but after a classic rookie mistake, the guys start to question whether Evan really has the chops to effectively manage the team.

Fill-a-Need, a start-up organization promoting autism awareness, wants OCC to build them a chopper. When Rick drops a bomb that he will be out of town for most of the build, Evan must rise to the challenge of both managing the project and fabricating the bike without Rick's help. Things go smoothly until Evan decides that he wants to change the design of the exhaust. Paul Senior forbids him to, wanting him to stick to the approved design, but Evan really wants to prove to Senior that his new version of the exhaust will take the bike to the next level. When Evan presents his new design to Senior, Senior is livid that Evan went behind his back and changed the design after being told not to. After deliberating with Steve and Ron, Senior decides to demote Evan to solely a fabricator. He just hopes Evan will stick around.

Ardbeg, a Scottish whiskey company, approaches OCC about building a trike -- the offspring of a tractor and a chopper. Now that Evan is no longer the creative director at OCC, he is able to step up his game as a strong fabricator without the pressure of a build falling entirely on his shoulders. Christian gets heat from Senior for doing his own thing when making a set of handlebars. He's been working for Senior for 11 years, and he's starting to feel undervalued. It takes Rick, the Senior Whisperer, to teach the guys how to manipulate him and ultimately get what they want while keeping him happy, too. As dysfunctional as it is, Christian comes to realize he wouldn't trade his OCC family for anything.

Sonic, the world's first fast-food restaurant, would like OCC to build them a bike that mixes their old-school classic roots and the modernization of the brand. Jason designs an old-school-meets-new-school bike for the company. The mock-up goes smoothly and the guys end up competing in a roller derby, giving them the chance to bond, get out of the office and have some fun. However, pressure mounts toward the end of the assembly when a chrome-bubbling issue threatens to keep the bike from being done on time for the looming reveal date. Christian, Rick and Evan band together to try to finish the bike and make it to the reveal in San Diego on time.

A high-end client from China asks Paul Senior and the team to build a one-of-a-kind bike inspired by the Year of the Dragon. It's a tall order and a complex design, but Senior and his team take on the challenge. A prank gone wrong destroys a part of the bike, and tensions rise as a mad dash begins to recreate the damaged part before the client returns to the States for the big reveal.

Gap Vax, the manufacturer of industrial vacuum trucks, commissions a bike from OCC to be revealed on Gap Vax's 25th Anniversary. Just as the guys are getting started on the chopper, Jersey Shore's Pauly D makes an unexpected visit to OCC, asking Paul Senior to build him a bike for a charity he's supporting. With the deadlines looming for both bikes, the guys work hard to finish the builds on time. The guys also manage to pull what they believe to be the ultimate prank on Senior.

Steve approaches Paul Senior about the idea of expanding the OCC brand and offering the public a chance to own an affordable and customizable Orange County Choppers motorcycle. Senior loves the idea and Jason gets to work designing a large display unit that could be installed in dealerships and retail outlets, showcasing the new bike designs. The pressure is on to get both bikes built in time for a major gathering with investors and retailers. In the midst of it all, Shaquille O'Neal shows up at OCC to order a very large custom chopper.