Tests 72 · 1 test Owners 85 · 16 reviews
Best test result: #3 of 6 in 2020 Motorcycle Sports Touring Tyre Test (dry braking)
Head-to-head
Updated
Dunlop RoadSmart III 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 1 + 1 road tests and 16 + 184 owner reviews. How we score
Too close to call: RoadSmart III and Diablo Rosso IV are level at 80.
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Tests 75 · 1 test Owners 85 · 184 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.
-
77
Dry
Level77Why this score
Source RoadSmart III Diablo Rosso IV Professional tests (TWG score) · 1 / 1 tests 72 68 Reviews found online 85 92 RoadSmart III: 60% × 72.1 + 40% × 85.3 = 77
Diablo Rosso IV: 60% × 67.7 + 40% × 91.5 = 77
-
83
Wet
Diablo Rosso IV +184Why this score
Source RoadSmart III Diablo Rosso IV Professional tests (TWG score) · – / 1 tests ≈ 80 (est.) 81 Reviews found online 87 87 RoadSmart III: 60% × 79.9 (est.) + 40% × 87.4 = 83
Diablo Rosso IV: 60% × 81.4 + 40% × 87 = 84
No road tests of wet for RoadSmart III. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.55).
-
78
Comfort
Diablo Rosso IV +280Why this score
Source RoadSmart III Diablo Rosso IV Professional tests (TWG score) ≈ 71 (est.) ≈ 72 (est.) Reviews found online 82 85 RoadSmart III: 40% × 71.4 (est.) + 60% × 81.8 = 78
Diablo Rosso IV: 40% × 72 (est.) + 60% × 84.7 = 80
No road tests of comfort for RoadSmart III. 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).
-
76
Treadwear
RoadSmart III +571Why this score
Source RoadSmart III Diablo Rosso IV Professional tests (TWG score) ≈ 72 (est.) ≈ 69 (est.) Reviews found online 83 75 RoadSmart III: 60% × 72.3 (est.) + 40% × 82.5 = 76
Diablo Rosso IV: 60% × 69.4 (est.) + 40% × 74.6 = 71
No road tests of treadwear for RoadSmart III. 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).
-
86
Handling (owners)
Diablo Rosso IV +591Why this score
Source RoadSmart III Diablo Rosso IV Reviews found online 86 91
Scores at a glance
| Category | Dunlop RoadSmart III | Pirelli Diablo Rosso IV |
|---|---|---|
| Relative Score | 80 | 80 |
| Dry | 77 | 77 |
| Wet | 83 | 84 |
| Comfort | 78 | 80 |
| Treadwear | 76 | 71 |
| Handling (owners) | 86 | 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
NotLessNeutralImportantMost
Recomputed
Headline score
80
/ 100
RoadSmart III
80
/ 100
Diablo Rosso IV
The professional test results behind the scores
Per discipline: the average % of the best tire over every test both tires were in, and how many of those tests each one won. “Different tests” rows compare results from separate tests.
| Discipline | Category | RoadSmart III | Diablo Rosso IV | Δ | Head-to-head |
|---|---|---|---|---|---|
| Also published by the testers (not in the score) | |||||
| Overall Ranking | Overall | #2/6 2020 Motorcycle Sports Touring Tyre Test | #5/12 2025 Sport and Hypersport Motorcycle Tyre Test | – | Different tests |
Pros, cons & observations
Themes extracted from owner reviews found online — not the opinion of TireWheelGuide.
Tire A RoadSmart III
Pros
- Exceptional tread life and mileage compared to dedicated sport tires.
- Sharp, responsive steering and handling characteristics.
- Consistent and reliable grip in both dry and wet road conditions.
Cons
- Occasional reports of rear-end slippage during aggressive cornering with power input.
- Front tire wear can be uneven or faster than expected depending on suspension setup.
- Some users noted a firm ride quality due to the stiff carcass construction.
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 · Dunlop RoadSmart III | B · Pirelli Diablo Rosso IV |
|---|---|---|
| Category | Summer | Summer |
| Vehicle type | Motorcycle | Motorcycle |
Which one should you actually buy?
80
/ 100
Dunlop RoadSmart III
80
/ 100
Pirelli Diablo Rosso IV
Too close to call: Dunlop RoadSmart III and Pirelli Diablo Rosso IV are within 2 points overall. Dunlop RoadSmart III is stronger on treadwear. Dunlop RoadSmart III rests on little evidence so far (1 test, 16 reviews), so read this result as provisional.
Pick tire A
You want the longest tread life
Dunlop RoadSmart III scores 76 vs 71 on treadwear.
Tire A · Dunlop RoadSmart III
Tire B · Pirelli Diablo Rosso IV
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RoadSmart III or Diablo Rosso IV?
Which is better in the wet, RoadSmart III or Diablo Rosso IV?
Neither, by our numbers: 83 vs 84 on the wet score, within 3 points.
Which grips better on dry roads, RoadSmart III or Diablo Rosso IV?
Neither, by our numbers: 77 vs 77 on the dry score, within 3 points.
Which is more comfortable, RoadSmart III or Diablo Rosso IV?
Neither, by our numbers: 78 vs 80 on the comfort score, within 3 points.
Which lasts longer, RoadSmart III or Diablo Rosso IV?
Dunlop RoadSmart III, 76 vs 71 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