Read the result

The car drawing fills in as you go, and the result card appears below it when the lap closes. Read it in this order.

1. Confidence first

Every result is rated High, Medium or Low, with the reasons in plain words. A Low result is not necessarily wrong, but it is not evidence: measure again before adjusting anything. The reasons the app can give:

• The phone drifted close to its limit.
• Some readings did not agree with each other.
• The measurement did not close cleanly.
• A walk between readings took a long time.
• The phone was knocked or spun during a walk.
• The bracket calibration is missing. Run the bracket calibration.
• The lap took a long time after the starting rest.
• This phone graded Marginal (or Not suitable) in the bracket calibration.

2. The numbers

Front total toe

The two front wheels against each other: the number a spec sheet gives. + is toe-in, − toe-out. Toe

Each front wheel’s toe

Above each wheel, for example Toe 0.16° R: the front of the tire points 0.16° right.

Steering

Steer-ahead: which way the steering wheel will be turned when you drive straight. Near zero is right. Steer-ahead

Rear total toe

Not adjustable on most cars, but it sets the thrust line.

Thrust

Which way the rear axle points the car, L or R; within 0.10° it is called straight. Needs Thrust ticked. Thrust angle

Camber

Under each wheel; negative means the top leans in. Cross camber sits inside the car at each axle. Camber

3. The spec check

Each number is checked against your vehicle’s specs, or the generic targets if it has none, and shown with words as well as colour:

• In spec
• Near the limit — check again
• Low by 0.08° or High by 0.08°

Camber is checked only when it is floor-corrected and calibrated. Old readings are checked again by the app’s latest rules each time you open them.

4. What to adjust

One line per front wheel: turn the front of the tire in or out, and by how much, to reach the middle of the front toe spec (on generic targets, +0.05° per wheel). Within 0.02° it says no change. With no toe spec, the target is half the measured total, which straightens the steering wheel without changing the total.

Then adjust toe safely.

Saved by itself

The lap saves itself on the phone; nothing is uploaded. Every result carries the notice: Estimate made with Rim Reader, a consumer measuring aid, not a certified alignment. Readings can be wrong. Have the alignment verified by a qualified shop. History, reports and sharing