345/30 R21 Tyres

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Potenza Sport

345/30R21 Y (111)

4.0/5

(2 reviews)

C
Fuel Efficiency

Fuel Efficiency / Rolling Resistance: C
How much fuel the tyre uses as it rolls. Graded A to E, where A is the most efficient and E the least.
D
Wet Grip

Wet Grip / Braking Performance: D
How well the tyre stops in the wet. Graded A to E, where A is the shortest stopping distance. Each grade is worth roughly 3 metres, about a car length.
B73 dB
External Noise

Noise Emission / Exterior Noise: B (73 dB)
How loud the tyre is from outside the car, measured in decibels. Graded A to C, where A is the quietest.

Car

Car tyre:
Designed for cars, rather than vans, 4x4s or commercial vehicles.
Reinforced (XL)

Extra Load or Reinforced tyres:
A stronger sidewall lets this tyre carry more weight than a standard tyre of the same size. Marked XL on the sidewall.

Fit from:18-10-2026

Fully Fitted Price

^£453^.97

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You've viewed 1 of 1 products

345/30 R21 Tyre Reviews

Overall rating4.0/5

Based on 2 reviews

Reeva B.

The performance was unsatisfactory; these tyres are designed to work well in wet and damp conditions, however they easily lose grip during acceleration. Cornering is not any better…

Bridgestone Potenza Sport

Shreya Stamp

I think they do a great job in different conditions except for on ice.

Bridgestone Potenza Sport

345/30 R21 Tyre Reviews

4.0/52 reviews

Showing 1–2 of 2 reviews

About these reviews

Tyre reviews recording 345/30 R21, across tyre brands and tread ranges. Each review identifies its tyre range.

3/5

The performance was unsatisfactory; these tyres are designed to work well in wet and damp conditions, however they easily lose grip during acceleration. Cornering is not any better and there is excessive understeer and sliding. Not ideal for this time of year.

5/5

Bridgestone Potenza Sport

I think they do a great job in different conditions except for on ice.

Performance cars like the Koenigsegg Jesko have 345/30 R21 rear tyre sizes. 345 is the width in millimetres; 30 is the aspect ratio of the sidewall, which in this case is 30% of 345, or 104mm. Then the 'R' of 'R21' confirms this is a radial tyre which is mounted to a 21-inch rim. This means the tyre has an overall diameter of 740mm. The Jesko has this sidewall in a staggered set of rear tyres with front tyres of a narrower size. We sell 345/30 R21 XL tyres at Tyres.co.uk.

Part of the size	Value	What it means
Section width	345	The width of the tyre across the tread, measured in millimetres.
Profile (aspect ratio)	30	Sidewall height as a percentage of the width - here, 30% of 345 mm (about 104 mm).
Construction	R	Radial construction, which is what nearly all road tyres use.
Rim diameter	21	The wheel diameter the tyre fits, measured in inches.