|Silver Bullet 2|
|Dimensions|| Diameter: 56.8mm |
Trapeze Width: 19mm
String Gap Width: Adjustable
|Bearing size||Size I Tom Kuhn|
|Response system||1999 onwards: Tom Kuhn Turbo Discs (as of current)|
It was also one of the fastest spinning yo-yos of its time, clocked at 14,300 revolutions per minute (RPM), or a rim speed of 100 miles per hour (mph). This rating was achieved by U.S. National Grand Master, Dale Oliver, in 1991.
The yo-yo was based on a pre-production model, the Turbo-Yo, of which only 39 were produced. Each Turbo-Yo came with a string gap adjustment tool (a screwdriver), and two large rubber washers that can be fitted on the yo-yo as centrifugal weights. At one point, Dr. Kuhn himself had used a Turbo-Yo with the rubber washers equipped to it, and had performed no less than 102 Around the World's with it before returning the yo-yo to his hand.
On July 31st, 1992, an SB-2 yo-yo was sent up into space by NASA on the Atlantis space shuttle for an "Around-the-World" ride where the yo-yo was employed as a prop for an educational video. Astronaut Jeffery Hoffman had put the SB-2 through zero gravity maneuvers, including slow-motion yo-yoing. That SB-2 had traveled 3,321,007 miles and went "around the world" 127 times before the shuttle returned to Earth.
Originally offered in an anodized Tortoise Shell and bare aluminum, the SB-2's colorways were later expanded to red, blue, and gold (yellow), and expanded again in 1995 to include violet, and three splash-anodized color schemes; Gamma, Infra-Red, and Ultra-Violet. At one point, a few promotional SB-2 yo-yos were produced for the Wells Fargo banking company. Some colorways, however, never make it past the prototype stage, making them all the more unique.
In 1999, a new version of the yo-yo, nicknamed the "SB-2.2", was released and it came packaged with Tom's patented Turbo Disc response system, eliminating the need to double-loop the string around the axle. The color choices were again expanded to include an additional splash anodized color scheme, and four models combining splash anodized hubs with polished bare aluminum rims.
Also released was a Butterfly-shaped variant, the Tom Cat.
- SB-2 Tortoise #1 at the Museum of Yo-Yo History
- Wells Fargo promotional SB-2 at the Museum of Yo-Yo History
- Turbo-Yo at the Museum of Yo-Yo History
- SB-2 Superman prototype #1 of 2 at the Museum of Yo-Yo History
- Galactic Blast.3 SB-2 prototype #1 of 2 at the Museum of Yo-Yo History
- SB-2 in Space postcard at the Museum of Yo-Yo History
- SB-2 postcard at the Museum of Yo-Yo History
- Tom Kuhn Turbo-Yo @ cornellouis' Tumblr page
- Tom Kuhn SB-2 Green Machine prototype #1 of 3 @ yoyobrothers' Online Instagram page