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Bridgestone Battlax Hypersport S21 vs Pirelli Diablo Rosso IV — Compared

Relative Score (0–100): the weighted average of the categories below, each 60% road tests and 40% owner reviews (comfort 40/60). Based on 0 + 1 road tests and 7 + 181 owner reviews. How we score

Diablo Rosso IV is ahead, 80–74

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Pirelli Diablo Rosso IV
Tire BPirelli

Diablo Rosso IV

Summer

± 7

Tests 75 · 1 test Owners 85 · 181 reviews

Best test result: #5 of 12 in 2025 Sport and Hypersport Motorcycle Tyre Test (wet handling)

Category by category

Relative Score per category, 0–100. Open “Why this score” for the tests and owner ratings behind it.

  1. 77

    Dry

    Level
    77
    Why this score
    SourceBattlax Hypersport S21Diablo Rosso IV
    Professional tests (TWG score) · – / 1 tests≈ 74 (est.)68
    Reviews found online8292

    Battlax Hypersport S21: 60% × 73.8 (est.) + 40% × 81.7 = 77

    Diablo Rosso IV: 60% × 67.8 + 40% × 91.9 = 77

    No road tests of dry for Battlax Hypersport S21. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.42).

  2. 76

    Wet

    Diablo Rosso IV +8
    84
    Why this score
    SourceBattlax Hypersport S21Diablo Rosso IV
    Professional tests (TWG score) · – / 1 tests≈ 75 (est.)82
    Reviews found online7887

    Battlax Hypersport S21: 60% × 74.8 (est.) + 40% × 78.1 = 76

    Diablo Rosso IV: 60% × 81.7 + 40% × 87.1 = 84

    No road tests of wet for Battlax Hypersport S21. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.55).

  3. 73

    Comfort

    Diablo Rosso IV +7
    80
    Why this score
    SourceBattlax Hypersport S21Diablo Rosso IV
    Professional tests (TWG score)≈ 70 (est.)≈ 72 (est.)
    Reviews found online7485

    Battlax Hypersport S21: 40% × 70.1 (est.) + 60% × 74.4 = 73

    Diablo Rosso IV: 40% × 72.1 (est.) + 60% × 85.3 = 80

    No road tests of comfort for Battlax Hypersport S21 or Diablo Rosso IV. The test half is the tested tires’ average (69): owners’ comfort ratings barely follow the road tests.

  4. 63

    Treadwear

    Diablo Rosso IV +8
    71
    Why this score
    SourceBattlax Hypersport S21Diablo Rosso IV
    Professional tests (TWG score)≈ 64 (est.)≈ 69 (est.)
    Reviews found online6074

    Battlax Hypersport S21: 60% × 64.1 (est.) + 40% × 60.3 = 63

    Diablo Rosso IV: 60% × 69 (est.) + 40% × 74.4 = 71

    No road tests of treadwear for Battlax Hypersport S21. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.35).

    No road tests of treadwear for Diablo Rosso IV. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.35).

  5. 83

    Handling (owners)

    Diablo Rosso IV +8
    91
    Why this score
    SourceBattlax Hypersport S21Diablo Rosso IV
    Reviews found online8391
Scores at a glance
CategoryBridgestone Battlax Hypersport S21Pirelli Diablo Rosso IV
Relative Score 74 80
Dry 77 77
Wet 76 84
Comfort 73 80
Treadwear 63 71
Handling (owners) 83 91

Higher is better. The Relative Score follows your weights below; category scores do not change.

Weight the categories that matter to you

Wet grip starts at “Important”. Treadwear starts at “Neutral” here: road tests measured it for at most one of the two tires, so it rests on owner reviews. Move the sliders and the scores update instantly.

Important
NotLessNeutralImportantMost
Important
NotLessNeutralImportantMost
Less important
NotLessNeutralImportantMost
Neutral
NotLessNeutralImportantMost
Less important
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Recomputed
Headline score
± 8

Battlax Hypersport S21

± 7

Diablo Rosso IV

Pros, cons & observations

Themes extracted from owner reviews found online — not the opinion of TireWheelGuide.

Tire A Battlax Hypersport S21

Pros

  • Exceptional dry grip and cornering stability
  • Rapid warm-up time
  • High performance capability suitable for track days

Cons

  • Limited tread longevity
  • Rapid wear on the center compound during straight-line riding
  • Reduced traction on painted road markings and pedestrian crossings
All owner themes in the Battlax Hypersport S21 review

Tire B Diablo Rosso IV

Pros

  • Exceptional dry and wet grip with a high level of rider confidence
  • Fast warm-up time and predictable handling at deep lean angles
  • Improved steering precision and turn-in compared to previous generations like the Diablo Rosso III

Cons

  • Higher price point compared to some competitors and previous models
  • Noticeable reduction in grip and increased rear wheel spin as the tires wear down
  • Requires full operating temperature for optimal performance late in its life cycle
All owner themes in the Diablo Rosso IV review

Specs side by side

Attribute A · Bridgestone Battlax Hypersport S21 B · Pirelli Diablo Rosso IV
CategorySummerSummer
Vehicle typeMotorcycleMotorcycle

Which one should you actually buy?

Bridgestone Battlax Hypersport S21

Pirelli Diablo Rosso IV

Winner: Pirelli Diablo Rosso IV — better wet, treadwear and handling. It leads or ties in every category we score. Bridgestone Battlax Hypersport S21 rests on little evidence so far (0 tests, 7 reviews), so read this result as provisional.

Pick tire B Your priority is wet-weather safety

Pirelli Diablo Rosso IV scores 84 vs 76 on wet.

Pick tire B You want the longest tread life

Pirelli Diablo Rosso IV scores 71 vs 63 on treadwear.

Pick tire B You enjoy sharp, responsive handling

Pirelli Diablo Rosso IV scores 91 vs 83 on handling.

Pick tire B You want the most comfortable ride

Pirelli Diablo Rosso IV scores 80 vs 73 on comfort.

Tire A · Bridgestone Battlax Hypersport S21
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Tire B · Pirelli Diablo Rosso IV
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Battlax Hypersport S21 or Diablo Rosso IV?

Which is better in the wet, Battlax Hypersport S21 or Diablo Rosso IV?

Pirelli Diablo Rosso IV, 84 vs 76 on our wet score.

Which grips better on dry roads, Battlax Hypersport S21 or Diablo Rosso IV?

Neither, by our numbers: 77 vs 77 on the dry score, within 3 points.

Which is more comfortable, Battlax Hypersport S21 or Diablo Rosso IV?

Pirelli Diablo Rosso IV, 80 vs 73 on our comfort score.

Which lasts longer, Battlax Hypersport S21 or Diablo Rosso IV?

Pirelli Diablo Rosso IV, 71 vs 63 on our treadwear score.

How do we compare tires?

Every category score blends two independent signals. 60% comes from professional tire tests (braking distances, lap times, noise measurements), each result compared with every other tire in the same test and newer tests counting more. 40% comes from owner reviews found online, adjusted for how generously each site rates. Both use one scale: the average tested tire gets 70, the best 100. When a tire has only one of the two, the missing half is estimated from the other and the score stays closer to average; with no road test and fewer than five owner reviews it gets no score yet.

Handling is the exception: road tests measure it inside the dry and wet scores, so its own row comes from owner ratings only and starts as less important.

Community buzz from Reddit and forums is shown for context only — it never changes the score. Full methodology