StringSpec
String finder

Browse all 791

Head to head

Babolat RPM Blast 18 (1.20) vs RS RS Lyon 17L (1.20)

RS Lyon 17L (1.20) leads on 3 of 6 measurements. The widest gap is ball bite, where RS Lyon 17L (1.20) is 21 percentile points ahead. Every figure is a testing-machine result at a fixed reference tension.

Measured, side by side

Babolat

RPM Blast 18 (1.20)

Polyester · 18 ga

RS

RS Lyon 17L (1.20)

Polyester · 17L ga

Stiffness lower = softer, kinder on the arm
18956th pct
18349th pct
Tension loss lower = stays where you strung it
3660th pct
3762nd pct
Energy return higher = livelier, more free power
8741st pct
8844th pct
Spin potential higher = more spin off the string bed
5.159th pct
5.159th pct
Ball bite higher = grabs the ball harder
0.39118th pct
0.42239th pct
String friction lower = strings slide and snap back
0.07615th pct
0.08331st pct

Bars are percentile against all 791 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.

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.

Coming from RPM Blast 18 (1.20) at 52 lb

String RS Lyon 17L (1.20) at 53.8 lb 24.4 kg

Coming from RS Lyon 17L (1.20) at 52 lb

String RPM Blast 18 (1.20) at 50.3 lb 22.8 kg

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.

RPM Blast 18 (1.20) mains / RS Lyon 17L (1.20) crosses

Stiffness54th pct · 1 measured
Tension loss61st pct · 1 measured
Energy return42nd pct · 1 measured
Spin potential59th pct · 1 measured
Ball bite21st pct · 1 measured
String friction18th pct · 1 measured

RS Lyon 17L (1.20) mains / RPM Blast 18 (1.20) crosses

Stiffness52nd pct · 1 measured
Tension loss62nd pct · 1 measured
Energy return43rd pct · 1 measured
Spin potential59th pct · 1 measured
Ball bite35th pct · 1 measured
String friction28th pct · 1 measured

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.

RPM Blast 18 (1.20)

~22 hours of play

RS Lyon 17L (1.20)

~21 hours of play

Both strings in full

Every published measurement
StringGaugePriceStiff lb/inLoss %Power %SpinBite COFFriction COF
Babolat RPM Blast 18 (1.20) Polyester18$22.0018936875.10.3910.076
RS RS Lyon 17L (1.20) Polyester17Lfind18337885.10.4220.083

Add a third string RPM Blast 18 (1.20) in full RS Lyon 17L (1.20) in full