C7 is the light blue Wind Tunnel and the softest-reading graphic in the range. Pale blue is unusual on a helmet at this price and has aged better than almost any other colour on helmets generally.

What this helmet is — and what changed for the R

Two things make an inexpensive helmet worth owning rather than merely cheap: a current certification, and features you would otherwise pay extra for. This one has both — ECE 22.06, and a Pinlock lens supplied rather than sold.

🔵 Its predecessor scored 4/5 with MCN. The 4 R adds reworked air intakes, a revised spoiler and an improved visor action.

About the Wind Tunnel C7 graphic

Light blue occupies useful ground between the neutral solids and the shouting ones. It keeps a genuinely high value, so it does much of what a white helmet does for conspicuity in dull light, but it is a colour rather than an absence of one — which means it works alongside a motorcycle instead of disappearing next to it. It is also one of the few shades that has never belonged to a particular decade, so it will look current for longer than a saturated colour would. 🔵 Under a matt finish it holds handling marks well and dry dust less well, and printed graphics cannot be touched in if chipped.

The SHARP stars that belong to a different Thunder

🔵 The independent evidence that does exist for this platform comes from a road test rather than a laboratory — and it is of the predecessor. MOTORCYCLE NEWS rated the outgoing Thunder 4 SV 4/5, calling it „surprisingly good for less than £120".

That verdict describes the helmet this one replaced. The Thunder 4 R has not been independently tested.

HIRP, two shells and ECE 22.06

The structure is conventional and appropriate: an injection-moulded HIRP shell to spread the load and resist penetration, over a polystyrene liner that absorbs energy by permanently crushing.

🔵 A crushed liner does not recover. After a real impact the helmet is finished, whatever it looks like from outside.

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

Look after the visor and it will outlast the padding. Never wipe a dry visor — road dust is abrasive and dragging it across the surface leaves permanent fine scratches.

🔵 Wet it first, every time. The visor is scratch-resistant coated but not scratch-proof, and MT-QVSS makes replacing it straightforward when the time comes.

The integrated sun visor

The sun shield mechanism is the part of a helmet most likely to develop a rattle over years of use, and it is worth checking on any second-hand example. On a new one it should deploy and retract cleanly without play.

🔵 The Thunder 4 R SV's runs on a single slider and retracts fully into the shell.

Enlarged intakes and a revised spoiler

🔵 Honest framing: ventilation is the specification this platform has historically been weakest on, and the specification MT changed most for this generation. Enlarged intakes and a reworked spoiler are documented; the result is not independently measured.

We would rather tell you that than repeat the previous model's review as if it described this one.

Interior, fit and retention

🔵 Two outer shell sizes across seven helmet sizes means the fit at the size boundaries is less precise than on a three-shell helmet — a helmet at the top of the smaller shell carries thinner padding than one at the bottom of the larger.

Try the size the chart gives you rather than ordering by tape alone.

Intercom preparation and speaker pockets

🔵 Intercom provision on a 157-euro helmet is not a given, and it is one of the features that lifts this above typical entry-level full-face helmets — alongside the sun visor, the tool-free visor system and the supplied Pinlock lens.

The system itself, MT-B01 Rider Sync, is a separate purchase.

Where it sits in MT's range

🔵 If an independent safety rating is part of your decision, note that only MT's Track SV currently carries one — four SHARP stars. The Thunder 4 R SV has none, and the four-star „MT Thunder" and „Thunder 3" entries are earlier models.

Every MT in the range holds ECE 22.06.

When something wears out

🔵 A word on visor care, because it prevents most of the visor sales we make. Never wipe a dry visor — road dust is abrasive and dragging it across the surface leaves permanent fine scratches that flare against oncoming headlights at night.

Wet it first, every time. MT-QVSS makes replacing a scratched visor a ten-second job.

In the box

• MT Thunder 4 R SV helmet — Wind Tunnel C7 (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 — 1375D50C7203
• Colour — Wind Tunnel C7 — Matt, light blue
• 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)