Bowling ball core · Roto Grip

Roto Grip Rondure Core

The core inside the Roto Grip Rubicon line

An asymmetric core with early rev-up and high flare, built for medium to heavy oil. Balls with this core are no longer available at BowlersMart.

  • Asymmetric
  • RG 2.490
  • Diff 0.052
  • MB 0.011
Roto Grip Rondure symmetric core shape inside the ball

Specs

RG AT 15 LB

2.490

Early rev-up

Revs soonerRevs later

32% of the reactive and urethane balls we stock have a lower RG.

DIFFERENTIAL AT 15 LB

0.052

High flare

Less flareMore flare

75% of the reactive and urethane balls we stock have a lower differential.

MASS BIAS AT 15 LB

0.011

Mild asymmetry

MilderStronger

8% of the asymmetric reactive and urethane balls we stock have a lower mass bias.

RG How soon the ball revs up.Differential How much the ball can flare.Mass bias How asymmetric the core is.
Roto Grip Rondure Core specs by ball weight
Weight RG DifferentialDiff Mass biasMB
16 lb 2.480 0.050 0.012
15 lbUsed on this page 2.490 0.052 0.011
14 lb 2.530 0.052 0.009
13 lb 2.570 0.032 0.010
12 lb 2.590 0.029 0.008

Source: Roto Grip published specs, as shown on BowlersMart’s original Roto Grip Rondure core page (2022). RG and differential change with ball weight; use the row for the weight you throw. The highlighted 15 lb row is the one used on this page.

Looking for a ball like your Rubicon?

Balls with the Roto Grip Rondure Core are no longer available at BowlersMart. These in-stock balls have the closest RG and differential.

SWAG Judge Bowling Ball

SWAG Judge

SWAG Witness Reactive

Medium to heavy oil

Sale price $184.95 Regular price $289.95In stock
Radical Outer Limits Black Hole Bowling Ball

Radical Outer Limits Black Hole

Radical HK22C Solid Reactive

Heavy oil

Sale price $159.95 Regular price $259.95In stock
Radical No Doubt Hybrid Bowling Ball

Radical No Doubt Hybrid

Radical Advantage Plus Hybrid Reactive

Heavy oil, medium oil

Sale price $174.95 Regular price $259.95In stock
SWAG Black Dragon Hybrid Bowling Ball

SWAG Black Dragon Hybrid

SWAG Scorch Hybrid AP26

Heavy oil, medium to heavy oil

Sale price $159.95 Regular price $259.95In stock
Radical Deep Impact Bowling Ball

Radical Deep Impact

HK22C+ Hybrid Reactive

Heavy oil

Sale price $169.95 Regular price $259.95In stock
Brunswick Combat Solid Bowling Ball

Brunswick Combat Solid

Brunswick Alpha Premier Solid HK22C2 Reactive

Medium to heavy oil

Sale price $194.95 Regular price $289.95In stock

Balls with the Roto Grip Rondure Core

None of the 9 balls with the Roto Grip Rondure Core are in stock at BowlersMart right now.

Show 9 balls no longer available at BowlersMart
More bowling balls with the Roto Grip Rondure Core
Ball Cover First seen
Roto Grip Rubicon Bowling Ball Roto Grip eTrax-S20 Solid Reactive July 2020
Roto Grip Rubicon UC2 Bowling Ball Roto Grip eTrax-P20 Pearl Reactive December 2020
Roto Grip Rubicon EX Overseas Bowling Ball Roto Grip eTrax Pearl Reactive May 2022
Roto Grip Rubicon UC3 Bowling Ball Roto Grip Tour-ethane Pearl October 2021
Roto Grip Rubicon GT Overseas Bowling Ball Roto Grip MicroTrax Hybrid Reactive October 2020
Roto Grip Rubicon Extreme Overseas Bowling Ball Roto Grip MicroTrax P-20 Pearl Reactive June 2023
Roto Grip Rubicon Booster Overseas Bowling Ball Roto Grip ExtremeTrax Pearl Reactive March 2022
Roto Grip Rubicon Attack Overseas Bowling Ball Roto Grip Hyper Response Hybrid Reactive June 2022
Roto Grip Rubicon UC3 Trax Overseas Bowling Ball Roto Grip Tour Ethane Solid Urethane June 2022

Where the Roto Grip Rondure sits

Each dot is a core in balls we stock. Cores close together roll alike; the cover and layout decide the rest.

Storm Element Tour A.I. Core, RG 2.470, diff 0.035DV8 Larceny Core, RG 2.471, diff 0.028DV8 Renegade Core, RG 2.499, diff 0.040Track I-Core Gen4, RG 2.480, diff 0.053Brunswick Vintage Light Bulb Low RG Core, RG 2.568, diff 0.032Brunswick Dual Centric Core, RG 2.509, diff 0.047Ebonite Big Time Core, RG 2.508, diff 0.054Hammer Stacked LED Core, RG 2.545, diff 0.047Hammer Vindicator Core, RG 2.474, diff 0.053Radical Vexed Variant Asymmetric Core, RG 2.490, diff 0.045Radical Modified Intel Symmetric Core, RG 2.483, diff 0.032Motiv Affliction V2 Core, RG 2.480, diff 0.055900 Global Conduit A.I. Core, RG 2.590, diff 0.050Roto Grip GEM A.I. Core, RG 2.490, diff 0.057Hammer Obsession Tour Core, RG 2.469, diff 0.034Hammer Super Offset Core, RG 2.524, diff 0.053Hammer Gas Mask Core, RG 2.500, diff 0.058Ebonite Turbo Core, RG 2.517, diff 0.040Ebonite Centrex Symmetrical Mass Bias Core, RG 2.466, diff 0.056Motiv Excel Core, RG 2.550, diff 0.030Motiv Detonator Core, RG 2.470, diff 0.055Storm Solarion A.I. Core, RG 2.480, diff 0.054SWAG Insanity Symmetric Core, RG 2.520, diff 0.034SWAG Fusion Core, RG 2.540, diff 0.036SWAG Watcher Symmetric Core, RG 2.510, diff 0.048SWAG Executioner Asymmetric Core, RG 2.500, diff 0.051Motiv Predator V2 Core, RG 2.470, diff 0.054Storm C3 Centripetal Control Core, RG 2.490, diff 0.029Roto Grip Rondure MaxD Core, RG 2.500, diff 0.058Hammer Vibe Core, RG 2.510, diff 0.042Hammer Aftermath Core, RG 2.520, diff 0.052Brunswick Alert Core, RG 2.478, diff 0.037Brunswick Rampart Core, RG 2.502, diff 0.051DV8 Collision Core, RG 2.462, diff 0.052Track MC2 Asym Core, RG 2.473, diff 0.046Radical Evil Eye Symmetric Core, RG 2.495, diff 0.046Ebonite Iron Fist V2 Core, RG 2.473, diff 0.053Storm Surge Core, RG 2.580, diff 0.024Roto Grip Hyped UP Core, RG 2.500, diff 0.042Roto Grip Morph-Wing Core, RG 2.510, diff 0.051Brunswick Fury Core, RG 2.524, diff 0.038Motiv Sigma Core, RG 2.470, diff 0.047Roto Grip Hustle Core, RG 2.530, diff 0.030900 Global Blast A.I. Core, RG 2.470, diff 0.055900 Global Strobe A.I. Core, RG 2.510, diff 0.052Radical Guru Core, RG 2.503, diff 0.044Track I-CORE 3.0, RG 2.486, diff 0.056DV8 Unholy Core, RG 2.504, diff 0.051Brunswick Infinity Core, RG 2.521, diff 0.051Storm Catalyst A.I. Core, RG 2.480, diff 0.053Hammer Gauntlet Core, RG 2.501, diff 0.050Hammer Raw Hammer Core, RG 2.537, diff 0.038Storm Atmos A.I. Core, RG 2.530, diff 0.042Storm Booster Core, RG 2.540, diff 0.046Track Shuttle Core, RG 2.480, diff 0.040Brunswick Light Bulb Core, RG 2.524, diff 0.030Radical Sneak Attack Core, RG 2.544, diff 0.036Motiv Gear Core, RG 2.480, diff 0.034Hammer Huntsman Core, RG 2.470, diff 0.050Hammer Super LED Core, RG 2.632, diff 0.034Ebonite Enhanced V2 Core, RG 2.480, diff 0.048DV8 Dualistic Core, RG 2.496, diff 0.045Radical Vexed Asymmetric Core, RG 2.498, diff 0.036Motiv Quadfire Core, RG 2.550, diff 0.043Track Stealth Core, RG 2.482, diff 0.056Brunswick Tiered Hexagon Core, RG 2.540, diff 0.045Columbia 300 Piranha Core, RG 2.554, diff 0.043Storm Torsion A.I. Core, RG 2.470, diff 0.050Storm Element Max A.I. Core, RG 2.470, diff 0.055Storm Radius Core, RG 2.610, diff 0.020Roto Grip Rondure Tour X Core, RG 2.480, diff 0.034SWAG Unreal Core, RG 2.510, diff 0.047SWAG Craze Core, RG 2.520, diff 0.030SWAG Serpent Asymmetric Core, RG 2.510, diff 0.048Motiv Overload Core, RG 2.480, diff 0.050DV8 Duality Core, RG 2.480, diff 0.036Hammer Spheroid Core, RG 2.480, diff 0.048Motiv Apex Predator Core, RG 2.520, diff 0.055Brunswick Danger Zone Core, RG 2.501, diff 0.048Storm RAD-TQ Core, RG 2.560, diff 0.051Storm Velocity Core, RG 2.480, diff 0.051Hammer Modified LED Core, RG 2.586, diff 0.027Epic Spark Core, RG 2.540, diff 0.049Motiv Hadron Dual Density Core, RG 2.500, diff 0.045Track Criterion ID Core, RG 2.496, diff 0.047Brunswick Zone Asymmetric Core, RG 2.478, diff 0.048Ebonite Entity Core, RG 2.515, diff 0.052Roto Grip Rocker A.I. Core, RG 2.480, diff 0.050Motiv Flux Core, RG 2.570, diff 0.015DV8 Mantra Core, RG 2.498, diff 0.047Hammer Gas Mask Low Diff Core, RG 2.500, diff 0.034Roto Grip RST A.I. Core, RG 2.520, diff 0.055Motiv Impulse V2 Core, RG 2.550, diff 0.050SWAG APX V1 Core, RG 2.500, diff 0.042900 Global Magna A.I. Core, RG 2.490, diff 0.044Columbia 300 Pulse PowerCOR Core, RG 2.468, diff 0.045KR Strikeforce Launch Core, RG 2.530, diff 0.047900 Global Ellipse Asymmetric A.I. Core, RG 2.480, diff 0.050Motiv Halogen Core, RG 2.550, diff 0.037Storm C3 A.I. Core, RG 2.480, diff 0.031Motiv Gear APG Core, RG 2.470, diff 0.036Radical Snapshot Symmetric Core, RG 2.523, diff 0.050Hammer Huntsman Tour Core, RG 2.472, diff 0.036Hammer LED Core, RG 2.650, diff 0.015Storm Inverted Fe2 Core, RG 2.570, diff 0.046Storm Capacitor Core, RG 2.570, diff 0.022SWAG Judge Core (pictured: SWAG Judge Bowling Ball)1Hammer High Rev Offset Core (pictured: Hammer 3-D Offset Assault Bowling Ball)2SWAG Dragon Asymmetric Core (pictured: SWAG Black Dragon Bowling Ball)3Radical No Doubt Symmetric Core (pictured: Radical No Doubt Hybrid Bowling Ball)4Radical Outer Limits Asymmetric Core (pictured: Radical Outer Limits Black Hole Bowling Ball)5Radical Torpedo Asymmetric Core (pictured: Radical Torpedo Direct Hit Bowling Ball)6Roto Grip Rondure Core (pictured: Roto Grip Rubicon Extreme Overseas Bowling Ball)EARLY REV-UPMID-LANELATER REV-UPHIGH FLAREMEDIUMLOW FLARE2.442.482.522.562.602.642.680.0100.0200.0300.0400.0500.060RG at 15 lbDifferential at 15 lb← Revs up soonerRevs up later →More flare ↑Less flare ↓

Nearest cores, zoomed in

Hover or tap a dot for that core’s numbers. Click a dot to open its page. Drag to move around when zoomed in. The same RG and differential do not guarantee the same ball motion.

Same family: Roto Grip Rondure MaxD Core Same family: Roto Grip Rondure Tour X Core Same family: Roto Grip Rondure Tour Core

This core 1 Nearest cores Other cores

Nearest cores to the Roto Grip Rondure Core
Core Brand Shape RG Diff vs this core
SWAG Judge Bowling Ball1SWAG Judge CorePictured: SWAG Judge
 SWAG Asymmetric 2.490 0.052 Same RG and differential
Hammer 3-D Offset Assault Bowling Ball2Hammer High Rev Offset CorePictured: Hammer 3-D Offset Assault
 Hammer Asymmetric 2.489 0.053 RG −0.001 · Diff +0.001
SWAG Black Dragon Bowling Ball3SWAG Dragon Asymmetric CorePictured: SWAG Black Dragon
 SWAG Asymmetric 2.490 0.050 RG 0.000 · Diff −0.002
Radical No Doubt Hybrid Bowling Ball4Radical No Doubt Symmetric CorePictured: Radical No Doubt Hybrid
 Radical Symmetric 2.485 0.051 RG −0.005 · Diff −0.001
Radical Outer Limits Black Hole Bowling Ball5Radical Outer Limits Asymmetric CorePictured: Radical Outer Limits Black Hole
 Radical Asymmetric 2.499 0.051 RG +0.009 · Diff −0.001
Radical Torpedo Direct Hit Bowling Ball6Radical Torpedo Asymmetric CorePictured: Radical Torpedo Direct Hit
 Radical Asymmetric 2.480 0.052 RG −0.010 · Diff 0.000

Matches use 15 lb RG and differential.

Drilling and tools

Drilling layoutsLayout guides for symmetric and asymmetric ballsDual angle converterTurn a pin to PAP layout into a dual angle layout

Turn on JavaScript to compare with your ball.Balls with the Roto Grip Rondure CoreNone of the 9 balls with the Roto Grip Rondure Core are in stock at BowlersMart right now.Show 9 balls no longer available at BowlersMartMore bowling balls with the Roto Grip Rondure CoreBallCoverFirst seenRoto Grip Rubicon Bowling BallRoto Grip eTrax-S20 Solid ReactiveJuly 2020Roto Grip Rubicon UC2 Bowling BallRoto Grip eTrax-P20 Pearl ReactiveDecember 2020Roto Grip Rubicon EX Overseas Bowling BallRoto Grip eTrax Pearl ReactiveMay 2022Roto Grip Rubicon UC3 Bowling BallRoto Grip Tour-ethane PearlOctober 2021Roto Grip Rubicon GT Overseas Bowling BallRoto Grip MicroTrax Hybrid ReactiveOctober 2020Roto Grip Rubicon Extreme Overseas Bowling BallRoto Grip MicroTrax P-20 Pearl ReactiveJune 2023Roto Grip Rubicon Booster Overseas Bowling BallRoto Grip ExtremeTrax Pearl ReactiveMarch 2022Roto Grip Rubicon Attack Overseas Bowling BallRoto Grip Hyper Response Hybrid ReactiveJune 2022Roto Grip Rubicon UC3 Trax Overseas Bowling BallRoto Grip Tour Ethane Solid UrethaneJune 2022Where the Roto Grip Rondure sitsEach dot is a core in balls we stock. Cores close together roll alike; the cover and layout decide the rest.All coresSymmetricAsymmetricRoto Grip onlyAny brand900 GlobalBrunswickColumbia 300DV8EboniteEpicHammerKR StrikeforceMotivRadicalRoto GripSWAGStormTrack+−ResetZoom to this coreDV8 Larceny Core, RG 2.471, diff 0.028DV8 Renegade Core, RG 2.499, diff 0.040Track I-Core Gen4, RG 2.480, diff 0.053Brunswick

From Roto Grip’s description

Questions bowlers ask

What is the RG of the Roto Grip Rondure Core?

At 15 lb the Roto Grip Rondure Core has an RG of 2.490. It ranges from 2.480 to 2.590 across the listed weights.

What is the 14 lb RG of the Roto Grip Rondure Core?

At 14 lb the RG is 2.530.

What is the differential of the Roto Grip Rondure Core?

At 15 lb the differential is 0.052. The mass bias is 0.011.

Which bowling balls use the Roto Grip Rondure Core?

Roto Grip Rubicon Bowling Ball, Roto Grip Rubicon UC2 Bowling Ball, Roto Grip Rubicon EX Overseas Bowling Ball, Roto Grip Rubicon UC3 Bowling Ball, Roto Grip Rubicon GT Overseas Bowling Ball. 0 are in stock now.

Can I still buy a ball with the Roto Grip Rondure Core?

Balls with this core are currently unavailable at BowlersMart. Closest in-stock alternatives by RG and differential include SWAG Judge Bowling Ball, Radical Outer Limits Black Hole Bowling Ball, Radical No Doubt Hybrid Bowling Ball, SWAG Black Dragon Hybrid Bowling Ball, Radical Deep Impact Bowling Ball, Brunswick Combat Solid Bowling Ball.

How do the Roto Grip Rondure Core specs change by weight?

At 16 lb: RG 2.480, differential 0.050, mass bias 0.012. At 12 lb: RG 2.590, differential 0.029, mass bias 0.008.

How does the Roto Grip Rondure Core compare with my ball?

Type the ball you throw into the Compare with your ball box on this page. It shows the RG and differential side by side and saves your bag for every core page.

Sources and method

Specs. Roto Grip published specs, as shown on BowlersMart’s original Roto Grip Rondure core page (2022), as published by the manufacturer.

Baseline. The baseline is 212 in-stock, published reactive and urethane balls. Plastic and polyester covers, 2-piece, 3-piece and pancake cores, missing covers and missing RG or differential values are excluded.

Percentiles. Percentiles are the share of baseline balls with a strictly lower or higher value; ties are not counted.

Nearest cores. Nearest cores are ranked by distance on standardized 15 lb RG and differential, with the same symmetric or asymmetric shape preferred among near ties (distance bands of 0.1).

Mass bias. Mass bias is compared among asymmetric balls with numeric mass bias only.

Updated. Catalog and page updated 2026-10-16.

Next lesson

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