What's it like to work on Robert Pirsig's Zen motorcycle? Museum curators can tell you.

Author Robert Pirsig left greasy fingerprints on pages of his shop manual while working on his mystical motorcycle, the one in the enduring 1974 classic "Zen and the Art of Motorcycle Maintenance."

Years later, a few curators at the Smithsonian have an idea how he felt, because they've worked on the cycle, too.

That's because Pirsig's motorcycle, a 1966 Honda Super Hawk, will be exhibited at the Smithsonian’s National Museum of American History in Washington, D.C., starting April 15.

Learn more: How Robert Pirsig's cycle found a home in Smithsonian.

The exhibit, titled "Zen and the Open Road," includes Pirsig's Honda, some motorcycling gear, and manuals and documents that are part of his book and cycling odyssey.

How did conservators prepare those cherished objects for the museum? With care and precision, it turns out.

The exhibit pays homage to Pirsig's famous book ...

"'Zen and the Art of Motorcycle Maintenance' is such an iconic book that anything associated with it has the same level of mystique," says Janice Ellis, the museum's senior book and paper conservator. "It's American-born philosophy."

Ellis worked on the motorcycle manuals Pirsig took with him on the 1968 ride, a rare photocopy of the typed Zen manuscript, and other documents.

You'll see that copy of Pirsig's manuscript, one of 10 he sent to prospective publishers, next to his motorcycle, tools, leather jacket, helmet and a first edition of the book.

... but 1966 Honda Super Hawk is the star

Pirsig's conversational style puts readers on the cycle with the very first sentence. The Smithsonian exhibit anticipates visitor interest by putting the cycle on center stage. Museum staffers were also impressed.

Co-workers, even those not connected with the exhibit, began stopping by to see the cycle themselves. They were fascinated, almost reverent, says Dawn Wallace, an objects conservator for the American history museum. She headed the group that spent many hours preparing it for exhibit.

"When we told them this was the motorcycle that Pirsig rode, the one he based his book on, you could see a light come on in their eyes when they realized what they were looking at," Wallace says.

The project "is really personal to a lot of people," she says. "Everyone's excited to see it go on display."

Conservators meticulously preserved cycle

When the museum takes possession of an item, "we don’t immediately open the crates the things are in," says Paul Johnston, a Smithsonian transportation curator who specializes in maritime artifacts, motorcycles, race cars and road transportation.

"We put the crate in the environment that it's going to be in and we let it sit for between a week and a month," he says. "That lets it acclimate to the environment."

The cycle was in decent shape, despite having not been on the road for a few years.

"My husband and his son had ridden it years and years ago, and they had worked on it throughout their ownership," says Wendy Pirsig, widow of Robert Pirsig, who died in 2017 at age 88.

Robert Pirsig "did his own maintenance, as he wrote about extensively in his book. That was going on for decades."

Later in life, when Robert Pirsig was in a wheelchair, he worked on the cycle "with someone who was more physically fit than he was," Wendy Pirsig says.

"When the bike came into the museum, it had just some dirt, a little bit of built-up residue on some surfaces," Wallace says. "It had some surface corrosion, nothing really in-depth or problematic. It just needed a little TLC and cleaning."

"All we did was a surface cleaning, with some cotton swabs and cotton wipes to remove the surface dirt or any built-up grime," Wallace says.

"You could definitely see an improved appearance," she says. "The chromed parts, for example, definitely shone more than they did before. But it still retains that historic appearance."

It took as many as 75 hours for the work to be completed, Wallace says. All the work was done in house.

Pirsig’s motorcycle was handled with kid – er, nitrile – gloves

As you might suspect, museum staffers don't just roll a vehicle into an exhibit hall.

"Every object is different," Wallace says. "The motorcycle was a little more complicated because it's large, it's got a lot of different parts and materials and surfaces."

And while the cycle will never be kick-started to life inside the museum, "We needed to be aware of the motorcycle's working condition," Wallace says.

Wallace says she checks for things like:

• Scratches
• Corrosion
• Dents
• Structural problems

Conservators then determine what should be done. "Are there things that need to be repaired? Or are they considered historic? We don't want to alter the history of it," she says.

"We work with the curator to learn the story of the object and what is trying to be told," Wallace says.

Staffers work in an object lab, a workspace about the size of a single-car garage. The space allows them to position the motorcycle for photographs and move around it to thoroughly clean it.

That means the room can get dirty. "We're working with grease, grime, and with different types of cleaners and solvents," Wallace says.

The team wears nitrile gloves at all times, which protect workers and the metal, plastic and rubber components of the object they're working on.

"If you touch a metal object, you may not see anything, but over the years, the oils in your hands are going to etch into the metal," Wallace says. "That will attract dirt. And that dirt will attract moisture, which can cause corrosion."

Besides cleaning, "we make sure that all the cycle's fluids are drained," Wallace says.

If they sit for too long, engine and transmission oils can settle, build up and get hard and cause problems, she says. Brake fluid, for example, is hygroscopic, which means it absorbs water and moisture. That causes metal parts to corrode.

"We introduce a long-term lubricant, usually a silicone-based lubricant or spray, into the system," Wallace says.

"It goes through the oil lines, so even if the motorcycle isn't running, we're not going to have pistons and things getting seized or corroded inside."

Preparation work included:

• Draining the gas tank and protecting the interior against corrosion.
• Draining the oil in the engine and transmission and replacing it with long-term lubricant.
• Removing the battery and disposing of it responsibly.
• Removing as much surface corrosion as possible and adding a protective chemical barrier.

The cycle will be placed on its center stand in the exhibit hall. An additional support stand will be added to keep both wheels off the floor to prevent wear spots on tires.

Documents preserve a 'window for future generations'

One of Pirsig's books was a 182-page Honda shop manual on how to fix the motorcycle. Smithsonian conservators found Pirsig's greasy fingerprints on inside pages with engine pistons, crankshafts and clutches, proof he was referring to the manual while getting his hands dirty handling engine parts.

"That's what's so lovely about it," says Ellis, the paper conservator. "He clearly used the manual, and used it well, to the point of it falling apart and him repairing it with what he had on hand, which was electrical tape."

Early in his book, Pirsig exhaustively lists what he took on the motorcycle ride. Ellis and other staffers worked on some of them for inclusion in the exhibit.

"It was really interesting to see the things that he carried with him on his trip," Ellis says. "It's one thing to have the luxury of working on an artifact, but it's another to have an artifact that clearly shows the person behind it."

Why save Pirsig's papers?

Preserving papers, documents and books takes much time and effort. What's the benefit of all that work?

"You do it so your kids or grandkids can understand a little bit about the life and culture of the maker or the user of the artifact,” Ellis says. "It provides a window for future generations to see the past."

In Pirsig's manual, "I love the electrical tape and the grease and the greasy fingerprints, because they tell you the way and the extent to which it was used," she says.

"It helps you get a sense of the person. To say he was hands-on is clear when you look at the artifacts he had."

Here's how to see the Smithsonian's Pirsig exhibit

Robert Pirsig's Honda Super Hawk and other items will be on display at the Smithsonian Institution's National Museum of American History, 1300 Constitution Ave. NW, Washington, D.C., 20560.

You'll find the cycle and other items in the "America on the Move" exhibition on the museum's first floor, in the East Wing.

The museum is open from 10 a.m. to 5:30 p.m. every day, except for Dec. 25. Admission is free and no tickets are required. For more information, go to https://americanhistory.si.edu or call (202) 633-1000.

Photographs from Robert Pirsig's 1968 motorcycle ride are courtesy of Wendy Pirsig; museum photos are by Jaclyn Nash and are courtesy of the Smithsonian Institution's National Museum of American History. Sourcing for this story includes USA TODAY Graphics reporting and research and interviews with staff of the Smithsonian Institution's National Museum of American History. Other sources include Montana State University; The Robert Pirsig Association; National Maritime Historical Society; the International Journal of Motorcycle Studies; Sea History Magazine; and the National Institute of Health's National Library of Medicine. Special thanks to Melinda Machado, director of the National Museum of American History's Office of Communications and Marketing, Integrated Communications.