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Accelera
Accelera IOTA ST68 255/40R21
Accelera IOTA ST68 255/40R21
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The Accelera IOTA ST68 in 255/40R21 ships free from ThreePiece.us, with Affirm financing available at checkout and fast delivery from a nationwide warehouse network.
What 255/40R21 means
In the size 255/40R21, 255 is the section width in millimeters (10.04 in), 40 is the aspect ratio — the sidewall stands 40% as tall as the tire is wide, or 102.0 mm (4.02 in) — R denotes radial construction, and 21 is the wheel diameter in inches. That works out to an overall diameter of about 29.03 inches, turning roughly 695 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 102 — a maximum load of 1,874 lbs per tire. The speed symbol V corresponds to a maximum sustained speed of 149 mph.
Load Range B corresponds to a 4-ply rating.
Specifications
| Size | 255/40R21 |
| Service Description | 102V |
| Load Index | 102 |
| Speed Rating | V |
| Load Range | B |
| Section Width (mm) | 255 |
| Aspect Ratio | 40 |
| Temperature Grade | ATIRE RIM DIAMETER=21TIRE TYPE=TouringTRACTION=ATREAD WEAR=400TREAD DEPTH=UQTG=400 A AWARRANTY=40000 |
Frequently asked questions
What does 102V mean on the Accelera IOTA ST68?
102V breaks down as load index 102 — rated for 1,874 lbs per tire — with a V speed rating, good for a maximum sustained 149 mph.
Will 255/40R21 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 255/40R21, this tire matches your vehicle's fitment. If you're changing sizes, compare overall diameter to keep your speedometer and clearances right. See every 255/40R21 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.
Keep shopping
Shop all 255/40R21 tires, browse Accelera tires, see every Accelera IOTA ST68 size, or view all tires at ThreePiece.us.
- BRAND:
- Accelera
- MODEL:
- IOTA ST68
- SIZE:
- 255/40R21
- ASPECT RATIO:
- 40
- LOAD INDEX:
- 102
- LOAD RANGE:
- B
- SECTION WIDTH:
- 255
- SERVICE DESCRIPTION:
- 102V
- SPEED INDEX:
- V
- TEMPERATURE:
- ATIRE RIM DIAMETER=21TIRE TYPE=TouringTRACTION=ATREAD WEAR=400TREAD DEPTH=UQTG=400 A AWARRANTY=40000
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