21"

21-inch wheels are fitted to large SUVs, executive saloons and high-performance cars, from the factory or where the arches leave room. This section’s wheels are five-stud designs from 9 J to 11.5 J wide, with listed weights of 14.2 to 18.4 kg and load ratings from 700 to 1000 kg.

At 21 inches the tyre is a thin band around a large rim. With little sidewall to flex, the wheel takes more of each impact, and a sharp pothole edge can bend the rim or pinch the tyre against it. Ride quality then leans on the springs, dampers and correct tyre pressures.

Fit is precise at this size. Many of these wheels have a centre bore cut to one hub size, and offsets of up to ET 64 tuck a very wide rim inside the arch. That leaves little margin at the inner edge, where the strut, spring seat and brake lines run.

What to compare:

• Bolt pattern: 5×108, 5×112, 5×114.3, 5×120 or 5×130.
• Width: 9, 9.5, 10, 10.5 and 11.5 J. Staggered sets pair a narrower front with a wider rear.
• Offset: ET 15 to ET 64. Compare the inner and outer edge positions with the original wheel, not just the ET figure.
• Centre bore: 63.3, 64.1, 66.5, 70.5, 71.6, 72.6 or 82 mm. A bore cut to the hub needs no ring, while the 82 mm bore is closed down with a centring ring.
• Load rating: 700 to 1000 kg. Heavy SUVs need the higher figures, and each tyre’s load index must also cover half the axle load.
• Finish: two-tone satin black/titanium, platinum/black and bronze/black, high gloss silver, black painted, flat black and matt bronze.

Keep the rolling circumference close to the original, so the speedometer, stability control and four-wheel drive work as designed. Fit tyres with the load index and speed rating in the vehicle documents, often reinforced types at this size. Keep pressures at the vehicle maker’s figure for the load carried, as a soft tyre leaves the rim exposed.