Kirschbaum Spiky Shark 17 vs Yonex Poly Tour Drive 16L (1.25)

Measured, side by side

Bars are percentile against all 788 strings, and the marked side is the one that measures better, which is not always the one you want. A firmer bed is worse for your elbow and better for your control, and no measurement knows which of those you came for.

Which one wins, by problem

Each string's standing on the site's rankings, out of every measured string in the database. This is where a comparison stops being arithmetic and starts being a decision.

• More spin and shape

  Spiky Shark 1734th

  Poly Tour Drive 16L (1.25)41st

• Easier on my arm

  Spiky Shark 17651st

  Poly Tour Drive 16L (1.25)589th

• More control, less launch

  Spiky Shark 17103rd

  Poly Tour Drive 16L (1.25)144th

• More power and depth

  Spiky Shark 17728th

  Poly Tour Drive 16L (1.25)694th

• Plays the same for longer

  Spiky Shark 17730th

  Poly Tour Drive 16L (1.25)650th

• Lasts longer before it breaks

  Spiky Shark 1764th

  Poly Tour Drive 16L (1.25)84th

• Best feel and touch

  Spiky Shark 17733rd

  Poly Tour Drive 16L (1.25)686th

Swapping between them: what tension?

Bed stiffness is published at one reference tension, so the only honest conversion is to scale it. These are starting points from 52 lb, not prescriptions. The calculator takes your own tension.

Hybrid: what if you used both?

Estimated, not measured. No hybrid combination has been tested as a bed. These figures are the two strings' own lab measurements weighted by how much of the bed each one actually is. Treat them as a guide to which way a pairing moves, never as lab data.

Open this in the hybrid builder

Which goes dead first?

Estimated from tension loss, which is the only thing the database measures about ageing. This is when the bed stops playing the way you strung it, not when the string breaks.

Both strings in full

Add a third string Spiky Shark 17 in full Poly Tour Drive 16L (1.25) in full