05. “I Love My Job”
The YZ series of motocross competition models is sold globally—strongest in North America, but also spanning South America, Europe, Oceania and Asia. The riders are just as varied as the map: professionals in AMA Supercross, the Motocross World Championship and All Japan, plus weekend riders enjoying family rides or solo sessions.
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Some stay with YZs for life. Some ride them simply because it makes life better. And the YZ, in turn, is built by people inspired by those riders.
This series highlights the employees across departments who create the YZ, sharing their challenges and passion. The final story is with Suzuki Kazuhiro, responsible for casting production of YZ crankcases.
Casting work is brutal in summer heat and winter cold. Suzuki describes his role as creating the model used to produce the mold, then planning how to cast the designer’s intended shape while meeting quality requirements. A key part is designing the “plan”—the path that guides molten metal through the mold. He’s also involved in quality measures, including updating molds and correcting defects.
Most of the job is thinking—but it’s thinking done on the move, walking the site, observing, and working through problems.
For the YZ, Suzuki was responsible for crankcase casting and building the project from scratch. He explains that creating a new mold begins with modelling, then includes consultation with the production department to ensure the end result is easy to set up and assemble. It’s steady work with a long timeline—he says it can take several years before production begins.
Suzuki has previously handled crankcases for Yamaha’s Crossplane Concept three-cylinder “CP3” engine and twin-cylinder “CP2.” Those engines sit in major models, including the MT series and the YZF-R9, which has had a strong presence in racing this year.
Even so, Suzuki doesn’t describe CP3 or CP2 as his “masterpieces” because he wasn’t starting from zero—those molds were updates to an existing base. But he says he was highly motivated on every model. The truth is, he genuinely loves his current job.
He started on the casting side in production, but now works on the technology side, involved from the earliest stages of manufacturing. That role has increased interaction with other companies and departments—and Suzuki says it suits him and brings a strong sense of accomplishment.
Still, the YZ felt different. Because it was his first from-scratch project, he was extremely motivated to make it a great product, get it into production, and release it to the world.
That motivation shows up in the details. Suzuki says Yamaha manufacturing tends to care even about parts you can’t see. Performance and weight reduction matter, but so does doing the unseen work properly. With the YZ, that mindset intensifies: it’s a competition model, often maintained, and the crankcase is likely to be opened—meaning the “hidden” work becomes visible. Suzuki wants people to notice those areas and recognise the care taken.
Attention to detail also changed the process. The crankcase is split into left and right halves, with gears and transmission installed before the cases are joined. Previously, separate molds were used for crankcases 1 and 2. For the YZ, one mold produces cases 1 and 2 simultaneously—bringing benefits like a shorter manufacturing process, lower costs, and reduced management requirements.
But success required heavy trial and error. Suzuki notes that pouring molten metal takes just 0.15 seconds—an instant—but quality hinges on the temperature of the molten metal at the moment filling is complete. If it’s too low, defects are more likely. By developing a method that keeps that temperature higher, the team achieved better quality.
Those advances also improved downstream manufacturing. After casting there are more steps—heat treatment, shot blasting, deburring and impregnation. Shot blasting removes small burrs, reducing deburring work and helping create a uniform casting surface. Impregnation involves immersing parts in resin so resin fills areas at risk of oil or water leakage—eliminating those issues at the material stage and improving quality. Suzuki says these improvements allowed them to eliminate two processes and shorten delivery times by optimising the overall workflow.
Like others in this series, Suzuki has felt the pull of racing more strongly as the YZ’s results become real. He says he’d always had a sense of CP2/CP3-equipped bikes being raced, but with the YZ he didn’t often see outcomes. Hearing about wins and championships has changed that—events in America and Europe now feel personal because he was involved in the bike that achieved them.
Encouraged, Suzuki says he wants to keep supplying strong products so the team can keep hearing good results—not just next year, but for many years to come.
Perhaps that’s the point of the YZ: an evolution driven by passion, challenge, and mutual respect between the riders who push it—and the people who build it.