Tests – · none yet Owners 57 · 13 reviews
Head-to-head
Updated
Bridgestone S20 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 13 + 182 owner reviews. How we score
Diablo Rosso IV is ahead, 77–63
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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.
-
65
Dry
Diablo Rosso IV +1075Why this score
Source S20 Diablo Rosso IV Professional tests (TWG score) · – / 1 tests ≈ 66 (est.) 68 Reviews found online 64 86 S20: 60% × 66.1 (est.) + 40% × 63.5 = 65
Diablo Rosso IV: 60% × 67.8 + 40% × 86.3 = 75
No road tests of dry for S20. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.41).
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66
Wet
Diablo Rosso IV +1682Why this score
Source S20 Diablo Rosso IV Professional tests (TWG score) · – / 1 tests ≈ 67 (est.) 81 Reviews found online 65 83 S20: 60% × 67.5 (est.) + 40% × 64.8 = 66
Diablo Rosso IV: 60% × 81.4 + 40% × 82.5 = 82
No road tests of wet for S20. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.55).
-
65
Comfort
Diablo Rosso IV +1176Why this score
Source S20 Diablo Rosso IV Professional tests (TWG score) ≈ 68 (est.) ≈ 71 (est.) Reviews found online 64 80 S20: 40% × 67.6 (est.) + 60% × 63.5 = 65
Diablo Rosso IV: 40% × 70.9 (est.) + 60% × 80.1 = 76
No road tests of comfort for S20. 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).
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50
Treadwear
Diablo Rosso IV +2070Why this score
Source S20 Diablo Rosso IV Professional tests (TWG score) ≈ 57 (est.) ≈ 68 (est.) Reviews found online 39 71 S20: 60% × 56.7 (est.) + 40% × 39.4 = 50
Diablo Rosso IV: 60% × 68.3 (est.) + 40% × 71.4 = 70
No road tests of treadwear for S20. 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).
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67
Handling (owners)
Diablo Rosso IV +1986Why this score
Source S20 Diablo Rosso IV Reviews found online 67 86
Scores at a glance
| Category | Bridgestone S20 | Pirelli Diablo Rosso IV |
|---|---|---|
| Relative Score | 63 | 77 |
| Dry | 65 | 75 |
| Wet | 66 | 82 |
| Comfort | 65 | 76 |
| Treadwear | 50 | 70 |
| Handling (owners) | 67 | 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
NotLessNeutralImportantMost
Recomputed
Headline score
63
/ 100
S20
77
/ 100
Diablo Rosso IV
Pros, cons & observations
Themes extracted from owner reviews found online — not the opinion of TireWheelGuide.
Tire A S20
Pros
- Exceptional grip levels in both wet and dry conditions
- Progressive and predictable handling characteristics
- Strong performance during aggressive road riding and track use
Cons
- Very short tread life, particularly on high-torque motorcycles
- Rapid degradation and squaring off of the rear tire
- Front tire can be slow to reach optimal operating temperature
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
Specs side by side
| Attribute | A · Bridgestone S20 | B · Pirelli Diablo Rosso IV |
|---|---|---|
| Category | Summer | Summer |
| Vehicle type | Motorcycle | Motorcycle |
Which one should you actually buy?
63
/ 100
Bridgestone S20
77
/ 100
Pirelli Diablo Rosso IV
Winner: Pirelli Diablo Rosso IV — better treadwear, handling and wet. It leads or ties in every category we score. Bridgestone S20 rests on little evidence so far (0 tests, 13 reviews), so read this result as provisional.
Pick tire B
You want the longest tread life
Pirelli Diablo Rosso IV scores 70 vs 50 on treadwear.
Pick tire B
You enjoy sharp, responsive handling
Pirelli Diablo Rosso IV scores 86 vs 67 on handling.
Pick tire B
Your priority is wet-weather safety
Pirelli Diablo Rosso IV scores 82 vs 66 on wet.
Pick tire B
You want the most comfortable ride
Pirelli Diablo Rosso IV scores 76 vs 65 on comfort.
Tire A · Bridgestone S20
Tire B · Pirelli Diablo Rosso IV
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S20 or Diablo Rosso IV?
Which is better in the wet, S20 or Diablo Rosso IV?
Pirelli Diablo Rosso IV, 82 vs 66 on our wet score.
Which grips better on dry roads, S20 or Diablo Rosso IV?
Pirelli Diablo Rosso IV, 75 vs 65 on our dry score.
Which is more comfortable, S20 or Diablo Rosso IV?
Pirelli Diablo Rosso IV, 76 vs 65 on our comfort score.
Which lasts longer, S20 or Diablo Rosso IV?
Pirelli Diablo Rosso IV, 70 vs 50 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