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The Brain (full name: The Yo-yo with a Brain) by Yomega is a yo-yo with a centrifugal clutch, which makes it return to the thrower's hand automatically when the yo-yo starts to lose spin. It is also the very first yo-yo to feature an auto-return clutch system. This yo-yo is great for beginners, as it helps the user to develop a strong, hard throw and to get a good grasp on the sleeper.

Upon its original release in 1984, the Brain (which was originally named the "Phantom" in early company literature) had quickly became a worldwide best-seller for Yomega, and has put the company on the map that is the yo-yo industry. The Brain features a distinctive "Convex" or "Standard" body shape that resembles the Modified shape used by the ProYo, but with rounded side caps. This body design was also used by two other flagship models in Yomega's line-up; the Fireball, which was released five years after the Brain, and the ball bearing Raider, which came out in 1991.

It was even licensed to Bandai for the Hyper Yo-Yo line in 1997 as the Hyper Brain (Japanese: ハイパーブレイン), and on April 13th, 2013 as the Wild Claw (Japanese: ワイルドクロー).

At one point in 2012, the Brain was re-released with redesigned clutch arms.

The Brain's patent has since expired. This allows other manufacturers to produce their own auto-return yo-yos, such as the Australian Black Mamba yo-yos by Abbe Toys, and the Duncan Reflex.

How the clutch works[]

The plastic transaxle sleeve on the Brain's axle features an O-ring on one end, and that end is inserted in the body half that contains the clutch mechanism. The clutch consists of two adjacent plastic arms, which are weighted with metal balls and are connected to the inside rim of the yo-yo with springs. These arms also have teeth on the other ends around the area of the axle.

When spinning, the centrifugal force pushes these arms towards the rims, thereby compressing the springs. When the yo-yo begins to slow down, the springs engage, forcing the clutch arms to the center of the hub, where their teeth grip around the O-ring, causing the yo-yo to return using the momentum of the decreasing spin. Also helping are a pair of starbursts, which helps to grip the string as the clutch does its job. It also makes the yo-yo easy to wind up.

The clutch system can be disabled by removing the O-ring from the transaxle sleeve, allowing the Brain to sleep like a Fireball, but the user would still have to get the yo-yo to return manually.


  • Saber Wing Brain - Features a wing-shaped body for string tricks. Originally released in Bandai's Hyper Yo-Yo line as the Stealth Brain.
  • Brain Glow - Glow-in-the-dark variation.
  • Brain Executive Edition - Features gold springs and weights on the clutch mechanism.
  • The Jewel - Features a plastic jewel on the center for looks.
  • Wild Claw - 2010s Hyper Yo-Yo re-release with a claw motif.

Official Description[]


YOMEGA - The Yo-Yo with a Brain (1984)[]

YOMEGA, the Yo-Yo with a Brain, propels this ancient toy into the future. The patented brain spins and returns YOMEGA automatically, providing a simple introduction into the art of yo-yo play.

YOMEGA - The Yo-Yo with a Brain (Early 1990's)[]

A patented centrifugal clutch programs automatic returns and super long spin times!

Hyper Brain (1997)[]

Type D - Auto-return Type

Equipped with an auto-return system using a centrifugal clutch. Diameter about 59mm. Weight about 59 grams.

Infinite Illusions 1999 Spring/Summer Catalog[]

This is the first yo-yo to feature a patented clutch mechanism that causes the yo-yo to automatically return. Ideal yo-yo for beginners.


  • Coincidentally, the Brain had entered production about ten years after the original ProYo was patented.
  • Not only that, but the original Silver Bullet yo-yo had also started production the same year as the Brain.
  • In 1999, Tom Kuhn/What's Next Mfg. gave away promotional "No Brain" (the image of a human brain blocked by the "No" symbol) stickers and pins for their Fixed Axle Challenge. The No Brain symbol is made as a humorous jab at the Brain's auto-return functionality, as Tom Kuhn/What's Next were competing against Yomega at the time.


External Link[]