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Accelera
Accelera Iota ST68 285/45R21
Accelera Iota ST68 285/45R21
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Looking for a 285/45R21 tire? The Accelera Iota ST68 is available now at ThreePiece.us with free shipping on every order and Affirm financing at checkout.
What 285/45R21 means
In the size 285/45R21, 285 is the section width in millimeters (11.22 in), 45 is the aspect ratio — the sidewall stands 45% as tall as the tire is wide, or 128.2 mm (5.05 in) — R denotes radial construction, and 21 is the wheel diameter in inches. That works out to an overall diameter of about 31.10 inches, turning roughly 649 revolutions per mile. Overall diameter is what matters for speedometer accuracy and clearance when you change sizes, so compare it — not just the width — against your current tire.
The service description on this tire decodes to a load index of 109 — a maximum load of 2,271 lbs per tire. The speed symbol W corresponds to a maximum sustained speed of 168 mph.
Specifications
| Size | 285/45R21 |
| Service Description | 109W |
| Load Index | 109 |
| Speed Rating | W |
| Load Range | XL |
| Section Width (mm) | 285 |
| Aspect Ratio | 45 |
| Temperature Grade | TIRE RIM DIAMETER=21TIRE TYPE=TouringTRACTION=TREAD WEAR=TREAD DEPTH=UQTG=WARRANTY=40000 |
Frequently asked questions
Will 285/45R21 tires fit my vehicle?
Check the size molded into your current tire's sidewall or the tire placard inside the driver's door jamb — if it reads 285/45R21, this tire matches your vehicle's fitment. If you're changing sizes, compare overall diameter to keep your speedometer and clearances right. See every 285/45R21 tire in stock to compare options.
How fast does this tire ship?
Every order at ThreePiece.us ships free, with fast delivery from a nationwide warehouse network. Affirm financing is available at checkout.
What does 109W mean on the Accelera Iota ST68?
109W breaks down as load index 109 — rated for 2,271 lbs per tire — with a W speed rating, good for a maximum sustained 168 mph.
Keep shopping
Shop all 285/45R21 tires, browse Accelera tires, see every Accelera Iota ST68 size, or view all tires at ThreePiece.us.
- BRAND:
- Accelera
- MODEL:
- Iota ST68
- SIZE:
- 285/45R21
- ASPECT RATIO:
- 45
- LOAD INDEX:
- 109
- LOAD RANGE:
- XL
- SECTION WIDTH:
- 285
- SERVICE DESCRIPTION:
- 109W
- SPEED INDEX:
- W
- TEMPERATURE:
- TIRE RIM DIAMETER=21TIRE TYPE=TouringTRACTION=TREAD WEAR=TREAD DEPTH=UQTG=WARRANTY=40000
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