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Tips, deep-dives and explainers on everything wheel & tire fitment.

Article

How Speedometer Error Is Calculated

When you change tire size, your speedometer reading drifts. Here is exactly how the math works.

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Article

Wheel Offset & Backspacing Explained

ET, offset, backspacing — the difference between a perfect fitment and rubbing.

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Article

What Tire Size Difference Is Acceptable?

The 3% rule that pros use when plus-sizing or downsizing tires.

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Article

Can Bigger Wheels Damage Your Suspension?

What plus-sizing does to ride quality, bearings, and bushings.

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Article

Tire Pressure Explained: PSI, Load and Tire Size Changes

What PSI really means, why the door placard matters more than any online calculator, and how a tire size change can shift the right pressure.

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Article

Tire Load Index Explained: How Much Weight Can a Tire Carry?

Decode the number after your tire size — what kg per tire it represents, how it relates to speed rating, and why you must never go below the OEM rating.

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Article

Wheel Offset vs Backspacing: What Is the Difference?

Two ways of describing the same wheel geometry. Here is how offset (ET) and backspacing relate, when each is used, and how to convert between them.

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Article

Plus-Sizing Guide: How to Upgrade Wheel Size Safely

Plus-one and plus-two upgrades done right — keeping rolling diameter constant, picking the right tire width and offset, and knowing the comfort tradeoffs.

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