Red Blood Cell (RBC)
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MK1 YoYos - MK1 and Spinworthy Collaboration!

MK1 and Spinworthy present the RBC (Red Blood Cell)!

When YoYoExpert Forum member Spinworthy Glen first showed off his new wooden fixed axle yoyo called the 'bloodcell' we were in awe of the visual aesthetics and simplicity. It is also was one of the most interesting fixed axle yoyos to hold and throw!

MK1 joined forces with Glen and the idea was to take one of YoYoExpert Forum member Spinworthy Glen's wooden models (called the Bloodcell) and turn it into a metal responsive yoyo!

Rather than using an A sized bearing, they decided to use a smaller MR85 bearing that is only 8mm in diameter, the same as the wooden axle in the original wooden Bloodcell. This bearing combined with the same gap width as the original is intended to replicate the ideal play characteristics of fixed axle yoyos with the smoothness and power of metal. The result is a very reliably responsive yoyo, even with a dry bearing.

It was a challenge to design a lightweight hollow-bodied yoyo, but they manged to dial it in at 48g using 7068 Aluminum with a diameter of around 55mm.

It’s fast, lightweight, powerful and best of all, very reliably responsive. It’s a 0A beast and it might just be the best shoot the moon yoyo ever. We think this is one of the yoyos of the year!


rbc yoyo by spinworthy mk1

mk1 spinworthy red blood cell yoyo

Red Blood Cell (RBC) Specifications:
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Diameter: 55.00 mm / 2.17 inches
Width: 34.00 mm / 1.34 inches
Gap Width: 2.30 mm / 0.09 inches
Weight: 48 grams
Bearing Size: MR85
Response: Custom Pads
Material: 7068 Aluminum
Designed in: USA
Made in: China
Released: December 2021

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