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Sensei — Instructors at JKA Northern California

五段 · Godan Chief Instructor
Sensei Wauriman Borges, 5th Dan

Wauriman Borges

Wauriman Borges is a 5th Dan and a member of the United States National Team. He trained under Oswaldo Mendonça Jr. Shihan and Yoshizo Machida Shihan, the President of JKA Brazil, a lineage that has carried him to multiple national championships in both the United States and Brazil.

His floor is built on a commanding presence in kumite, with a precise mae-geri and a relentless ashi-barai that emphasize power, timing, footwork, and indomitable spirit. In 2024 he represented the USA at the JKA World Championships in Takasaki, Japan, advancing through the first two rounds before facing Japan in round three.

Since taking the helm in San Bruno he has shaped the dojo's culture around personal growth, discipline, and an open door for beginners and competitors alike. Favorite katas: Jitte and Sōchin.

5th Dan
Godan
JKA-certified
2024
JKA Worlds
Takasaki, Japan
USA
National Team
Active
Cert. Instructor C · Judge C · Examiner D
Sensei Wauriman delivers a mae-geri at the 2024 JKA World Championships in Takasaki, Japan
2024 JKA World Championships · Takasaki, Japan Sensei Wauriman's mae-geri against Japan.
四段 · Yondan Assistant Instructor

Harrison Rahn

Harry began studying martial arts as a child before taking up shotokan in 2013 at the Tulane Karate Club under Kyriakos and Dimitri Papadopoulos. He joined JKA NorCal in 2018, then spent several months at the JKA World Headquarters in Tokyo preparing for the 2024 World Championships.

A two-time Panamerican finalist and World semifinalist, he now helps foster the JKA NorCal Competition Team. He credits karate with the discipline behind every long goal he has set for himself, on the floor and off it.

One of his favorite memories is the roar of the US team after his first elimination-round win at the 2023 Panamerican Championships, the moment that crystallized why he keeps competing.

4th Dan
Yondan
JKA-certified
2×
Panamerican
Finalist
1×
World
Semifinalist
Harrison Rahn, 4th Dan
三段 · Sandan Assistant Instructor
Sammi Yeung, 3rd Dan

Sammi Yeung

Sammi Yeung has more than a decade with JKA NorCal. A women's kumite national champion and four-time United States National Team member, she has represented the country in kata, kumite, and team events at the highest levels of competition.

In 2025 she took individual gold in kata at the JKA Panamerican Championships and helped the US Women's team capture their first Team Kata and Team Kumite gold medals. At the 2024 Gichin Funakoshi World Cup the US Women's Team Kata placed 4th globally. Performing on the main tatami under the stadium lights, she remembers the adrenaline and the realization she was living a childhood dream.

Having graduated from the JKA-USA youth team to the adult team, she carries a perspective that resonates with younger students chasing the same path. She mentors members of the Competition Team and centers her teaching on a supportive, inclusive community.

4×
US National
Team Member
Gold
2025 Panam
Individual Kata
4th
2024 World Cup
Team Kata

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San Bruno · Five days a week · All levels

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