Pure is the plain line of the Thunder 4 R SV, and gloss white is the version that does most for you in traffic. On a helmet bought to be ridden every day rather than admired, that is the argument that matters.

What this helmet is — and what changed for the R

The Thunder 4 R SV is the evolution of the Thunder 4 SV, and the changes are specific: reworked air intakes, a revised spoiler and an improved visor-opening action — plus a Pinlock insert included as standard, which few rivals at this price manage.

🔵 MCN rated the outgoing Thunder 4 SV 4/5, calling it „surprisingly good for less than £120". That verdict belongs to the predecessor.

About the gloss white finish

Commuting is where a motorcyclist is least expected and most often looked through — a driver pulling out of a side road has a fraction of a second, in cluttered light, against a busy background. A white helmet sits at head height above the headlight, exactly where the eye scans, and it is resolved measurably sooner than a dark one. There is a thermal benefit alongside it on a helmet whose ventilation was the predecessor's noted weakness: a pale shell reflects solar load a dark one converts into interior heat. 🔵 The cost is dirt — road film and insect strike show on white sooner than on anything else in this range.

The SHARP stars that belong to a different Thunder

🔵 An important clarification. SHARP lists an „MT Thunder" and an „MT Thunder 3" at four stars — and those are different, earlier models. Neither the Thunder 4, the Thunder 4 SV nor this Thunder 4 R has been SHARP-tested.

Stars from a predecessor do not transfer to a successor. This helmet is untested rather than poorly rated, and we would rather say so than let the number drift onto this page.

HIRP, two shells and ECE 22.06

The shell is HIRP — High Impact Resistant Polymer — a high-strength thermoplastic MT tunes for impact resistance relative to weight, in two outer shell sizes across XS to 3XL.

🔵 Weight is roughly 1500 g ±50. MT has not published a separate figure for the 4 R; that number is the documented Thunder 4 SV / HIRP-platform weight.

MT-QVSS, the visor lock and the Pinlock in the box

The MT-V-28C main visor runs on MT-QVSS — the Quick Visor Swap System that made MT's name in this class — so it comes off and goes back on in seconds without tools. A lock holds it closed at speed.

🔵 A Pinlock® DKS435 MaxVision anti-fog insert is included in the box, which at this price is genuinely unusual.

The integrated sun visor

The integrated drop-down sun visor deploys with a single slider and retracts fully into the shell when it is not needed — glare protection the moment the sun comes out, with no stopping to swap visors or reach for sunglasses.

🔵 It is one of the features that lifts this helmet clear of typical entry-level full-face helmets, most of which have none.

Enlarged intakes and a revised spoiler

Ventilation was reworked for this generation: MT enlarged the air intakes on the 4 R specifically, alongside the revised spoiler and the improved visor action.

🔵 That is a targeted change rather than a marketing one. MCN's review of the outgoing Thunder 4 SV named ventilation as its main weakness — the 4 R's intakes are the answer to that criticism.

Interior, fit and retention

The lining is fully removable and washable, and retention is a micrometric ratchet — quick, precise and workable in gloves, which on a helmet fastened twice a day matters more than the theoretical advantages of a double-D ring.

🔵 Check the ratchet adjustment every few months. It should be snug enough that the helmet cannot be rolled forward off your head.

Intercom preparation and speaker pockets

The helmet is intercom-ready for MT's own MT-B01 (MT Rider Sync) system, with dedicated speaker pockets in the lining rather than space you have to make.

🔵 No system is supplied. Speaker pockets sized into the padding are the difference between an intercom you forget about and one that presses on your ear by hour two.

Where it sits in MT's range

The Thunder 4 R SV sits in the middle of MT's range: above the entry-level jets and below the carbon KRE+ S, which is the only MT built on a composite shell and the only one with FIM homologation.

🔵 Within the Thunder line, the „SV" is the sun visor and the „R" is this generation — the evolution of the Thunder 4 SV.

When something wears out

A nose deflector is supplied with the helmet, and so is the Pinlock DKS435 lens. Replacement visors, Pinlock lenses, cheek pads, linings and the sun visor are all separately available.

🔵 What cannot be replaced is a crushed EPS liner. After a real impact the helmet is finished, however it looks from outside.

In the box

• MT Thunder 4 R SV helmet — Pure A0 (HIRP shell)
• Clear MT-V-28C visor, fitted
• Pinlock® DKS435 MaxVision anti-fog insert
• Nose deflector
• 🔵 No intercom — the helmet is prepared for the MT-B01 Rider Sync system; the system is a separate purchase

Size guide

Specification

• Model — MT-Helmets Thunder 4 R SV
• Part number — 137500PA0103
• Colour — Pure A0 — Gloss white
• Homologation — ECE 22.06 — the current European standard
• 🔴 Safety rating — none. SHARP's four-star „MT Thunder" and „MT Thunder 3" are different, earlier models; the Thunder 4, 4 SV and 4 R have not been tested. No ADAC or Snell result either
• Independent verdict — MOTORCYCLE NEWS 4/5 — 🔴 for the predecessor Thunder 4 SV („surprisingly good for less than £120"), which named ventilation as its main weakness. No test of the 4 R exists yet
• Helmet type — Full-face, everyday / commuting
• Shell — HIRP (High Impact Resistant Polymer); two outer shell sizes
• Weight — approx. 1500 g ±50 — 🔴 MT publishes no separate figure for the 4 R; this is the documented Thunder 4 SV / HIRP-platform weight
• Sizes — XS to 3XL (seven sizes)
• Visor — MT-V-28C on the MT-M-28X mechanism, with MT-QVSS tool-free quick swap and a lock against unintended opening
• Anti-fog — Pinlock® DKS435 MaxVision included as standard
• Sun visor — integrated drop-down, single slider, retracts fully into the shell
• Ventilation — enlarged intakes and a revised spoiler for this generation — MT's answer to the criticism levelled at the Thunder 4 SV
• Retention — micrometric ratchet buckle
• Interior — fully removable and washable, with dedicated speaker pockets
• Communication — prepared for MT-B01 (MT Rider Sync) — system sold separately
• Also supplied — nose deflector
• Impact liner — expanded polystyrene — crushes once and does not recover; replace the helmet after any real impact
• Serviceability — visor, Pinlock lens, lining, cheek pads, sun visor and nose deflector all available separately
• Replacement guidance — after around five years of use regardless of condition, and immediately after any impact
• Manufacturer — MT-Helmets (MT Helmets, Spain)
• Sizing note — measure around the widest part of your head, about 1–2 cm above the eyebrows. With two outer shell sizes, try the size the chart gives you rather than ordering by tape alone — the fit at the shell boundary is less precise than on a three-shell helmet
• Made for — commuting, everyday riding and country roads at ordinary speeds — not a long-distance touring or track helmet
• Care — wash the lining by hand a few times a season; never wipe the visor or the sun visor dry, as road dust scratches both permanently

• 1x MT Thunder 4 R SV helmet
• 1x MT-V-28C clear visor (Pinlock Max Vision ready)
• 1x Pinlock DKS435 anti-fog insert
• 1x nose deflector
• Integrated drop-down sun visor (built in)