Yonex

Poly Tour Spin 16L (1.25)

Polyester Gauge 16L 1.27 mm In production

Lab measurements for Yonex Poly Tour Spin 16L (1.25), ranked against all 791 strings in the database. Every figure below is a testing-machine result at a fixed reference tension, not a playtest opinion.

Measured values

Stiffness

214lb/in

lower = softer, kinder on the arm

Tension loss

27%

lower = stays where you strung it

Energy return

89%

higher = livelier, more free power

Spin potential

6.3

higher = more spin off the string bed

Ball bite

0.632COF

higher = grabs the ball harder

String friction

0.100COF

lower = strings slide and snap back

How it ranks against all 791 strings

Stiffness 214 lb/in · 82nd pct

Stiffer than 82% of strings tested.

Tension loss 27 % · 41st pct

Sheds more tension than 41% of strings tested.

Energy return 89 % · 52nd pct

Livelier than 52% of strings tested.

Spin potential 6.3 · 83rd pct

More spin potential than 83% of strings tested.

Ball bite 0.632 COF · 98th pct

Grips the ball harder than 98% of strings tested — bites the ball hard through the brush.

String friction 0.100 COF · 63rd pct

More string-on-string friction than 63% of strings tested.

Like Poly Tour Spin 16L (1.25), but…

Almost nobody looks a string up out of curiosity. You are here because something about your current setup is wrong. Each list below keeps the rest of this string's profile as close as it can while moving decisively on the one thing you picked, so these are swaps rather than merely different strings.

SofterKinder on the arm

FirmerMore control, less launch

More spinBites and snaps back harder

More powerHands more back to the ball

Less powerLower launch, more control

Holds tensionStays where you strung it

What Poly Tour Spin 16L (1.25) is actually good for

Its standing on each of the site's rankings, out of every measured string in the database. Same arithmetic as the finder, not a separate opinion.

How long it lasts, and how far it stretches

Playable life

~28hours

Estimated from tension loss, on a scale running from 40 hours for the best-holding strings in the database down to 10 for the worst. At four hours a week that is about 7 weeks.

Estimated, not measured. This estimates when the bed goes dead, not when the string snaps. If you break strings before you notice them going dull, you are a breaker, and thickness and material matter far more to you than tension hold does.

Track this in a setup

Elongation under load

0.03.57.010.540 lb51 lb62 lb6.7%2.7%9.4%Pulled toStretch (%)
This stringDatabase median

How far the string stretches when tensioned to a given load. A string that elongates more absorbs more of the impact itself and feels softer; one that barely moves passes more of it on to the frame and the arm.

Measured at every tension and swing speed

The figures at the top of this page come from one test condition: 51 lb at fast swing speed. There are one in total, and all of them are below. Tension moves the bed more than the choice between two similar strings does, so this is the table that actually answers "what will it feel like for me".

Stiffness lb/in lower = softer, kinder on the arm

Strung at Fast swing
51 lb 23.1 kg 214

Tension loss % lower = stays where you strung it

Strung at Fast swing
51 lb 23.1 kg 27

Energy return % higher = livelier, more free power

Strung at Fast swing
51 lb 23.1 kg 89

The highlighted cell is the condition every other figure on this site is quoted at.

What else the machine recorded

Further measurements from the same test, given at the reference condition of 51 lb, fast swing.

Dwell time

33.7ms

How long the ball stays on the string bed. Longer dwell is the physical basis of what players call hold or pocketing.

Bed deflection

31.1mm

How far the string bed moves at impact. More deflection means the bed is doing more of the work of stopping the ball.

Peak force

34lb

The highest force perpendicular to the string bed during impact. The spike the frame and the arm actually receive.

Tension at impact

37.2lb

What the bed is actually pulled to by the time the ball arrives, after it has settled. Always lower than the tension it was strung at.

Loss: settling

3.4lb

Tension lost simply from being strung and left alone, before a ball is hit.

Loss: bedding in

10.2lb

Tension lost while the bed settles over its first impacts.

Loss: impact

0.2lb

Tension lost to the impact itself. Frequently negative, because a bed often gains tension across an impact rather than losing it.

Loss: total

13.7lb

The three losses above added together, in pounds.

Strings that play like this

Closest matches across stiffness, tension loss, energy return and spin potential.

Head to head: Poly Tour Spin 16L (1.25) vs Razor Code 18 (1.20) · Poly Tour Spin 16L (1.25) vs Black Code 4S 18 (1.20) · Poly Tour Spin 16L (1.25) vs Tecni-spin 16 (1.28)

More from Yonex

What these numbers mean

Stiffness · lb/in

How much the string bed resists deflection. Higher plays firmer and more controlled; lower plays softer and easier on the arm.

Tension loss · %

Share of the reference tension the string sheds under a fixed test protocol. Lower means the bed stays where you strung it for longer.

Energy return · %

Share of impact energy handed back to the ball. Higher plays livelier and more powerful.

Spin potential

Ball friction divided by string-on-string friction. Higher means better bite with a cleaner snapback, so more spin.

Ball bite · COF

String-on-ball friction. Higher grabs the ball harder through the brush.

String friction · COF

String-on-string friction. Lower lets the mains slide and snap back into place after impact.

Compare Poly Tour Spin 16L (1.25) against 791 strings Switching from this? Convert your tension Use it in a hybrid Find it on the map Find the right string for me