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Bridgestone Battlax BT 021 looks discontinued: no new owner reviews or road tests in five years and no current EU tyre label.

Head-to-head Updated

Bridgestone Battlax BT 021 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 10 + 182 owner reviews. How we score

Diablo Rosso IV is ahead, 77–67

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Pirelli Diablo Rosso IV
Tire BPirelli

Diablo Rosso IV

Summer

± 7

Tests 75 · 1 test Owners 81 · 182 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. 68

    Dry

    Diablo Rosso IV +7
    75
    Why this score
    SourceBattlax BT 021Diablo Rosso IV
    Professional tests (TWG score) · – / 1 tests≈ 68 (est.)68
    Reviews found online6886

    Battlax BT 021: 60% × 67.9 (est.) + 40% × 67.9 = 68

    Diablo Rosso IV: 60% × 67.8 + 40% × 86.3 = 75

    No road tests of dry for Battlax BT 021. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.41).

  2. 67

    Wet

    Diablo Rosso IV +15
    82
    Why this score
    SourceBattlax BT 021Diablo Rosso IV
    Professional tests (TWG score) · – / 1 tests≈ 68 (est.)81
    Reviews found online6683

    Battlax BT 021: 60% × 68.1 (est.) + 40% × 65.9 = 67

    Diablo Rosso IV: 60% × 81.4 + 40% × 82.5 = 82

    No road tests of wet for Battlax BT 021. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.55).

  3. 66

    Comfort

    Diablo Rosso IV +10
    76
    Why this score
    SourceBattlax BT 021Diablo Rosso IV
    Professional tests (TWG score)≈ 68 (est.)≈ 71 (est.)
    Reviews found online6480

    Battlax BT 021: 40% × 67.8 (est.) + 60% × 64.4 = 66

    Diablo Rosso IV: 40% × 70.9 (est.) + 60% × 80.1 = 76

    No road tests of comfort for Battlax BT 021. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.20).

    No road tests of comfort for Diablo Rosso IV. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.20).

  4. 66

    Treadwear

    Diablo Rosso IV +4
    70
    Why this score
    SourceBattlax BT 021Diablo Rosso IV
    Professional tests (TWG score)≈ 66 (est.)≈ 68 (est.)
    Reviews found online6671

    Battlax BT 021: 60% × 66.3 (est.) + 40% × 65.8 = 66

    Diablo Rosso IV: 60% × 68.3 (est.) + 40% × 71.4 = 70

    No road tests of treadwear for Battlax BT 021. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.36).

    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 0.36).

  5. 65

    Handling (owners)

    Diablo Rosso IV +21
    86
    Why this score
    SourceBattlax BT 021Diablo Rosso IV
    Reviews found online6586
Scores at a glance
CategoryBridgestone Battlax BT 021Pirelli Diablo Rosso IV
Relative Score 67 77
Dry 68 75
Wet 67 82
Comfort 66 76
Treadwear 66 70
Handling (owners) 65 86

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 BT 021

± 7

Diablo Rosso IV

Pros, cons & observations

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

Tire A Battlax BT 021

Pros

  • Exceptional tread longevity and durability for high-mileage commuters
  • Reliable performance for motorway and long-distance riding
  • Strong grip characteristics when tire pressures are correctly calibrated

Cons

  • Handling characteristics can feel unpredictable or heavy if pressures are not perfectly matched to the bike
  • Reports of poor wet-weather grip and lack of rider feedback
  • Tendency for the center of the tire to flatten out significantly during high-mileage motorway use
All owner themes in the Battlax BT 021 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 BT 021 B · Pirelli Diablo Rosso IV
CategorySummerSummer
Vehicle typeMotorcycleMotorcycle

Which one should you actually buy?

Bridgestone Battlax BT 021

Pirelli Diablo Rosso IV

Winner: Pirelli Diablo Rosso IV — better handling, wet and comfort. It leads or ties in every category we score. Bridgestone Battlax BT 021 rests on little evidence so far (0 tests, 10 reviews), so read this result as provisional.

Pick tire B You enjoy sharp, responsive handling

Pirelli Diablo Rosso IV scores 86 vs 65 on handling.

Pick tire B Your priority is wet-weather safety

Pirelli Diablo Rosso IV scores 82 vs 67 on wet.

Pick tire B You want the most comfortable ride

Pirelli Diablo Rosso IV scores 76 vs 66 on comfort.

Pick tire B You want the most grip on dry roads

Pirelli Diablo Rosso IV scores 75 vs 68 on dry.

Tire A · Bridgestone Battlax BT 021
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Tire B · Pirelli Diablo Rosso IV
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Battlax BT 021 or Diablo Rosso IV?

Which is better in the wet, Battlax BT 021 or Diablo Rosso IV?

Pirelli Diablo Rosso IV, 82 vs 67 on our wet score.

Which grips better on dry roads, Battlax BT 021 or Diablo Rosso IV?

Pirelli Diablo Rosso IV, 75 vs 68 on our dry score.

Which is more comfortable, Battlax BT 021 or Diablo Rosso IV?

Pirelli Diablo Rosso IV, 76 vs 66 on our comfort score.

Which lasts longer, Battlax BT 021 or Diablo Rosso IV?

Pirelli Diablo Rosso IV, 70 vs 66 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