As you say, I didn't spell out that part. You'll have to start again by clearing the settings, and to do that press the Start/Stop button on the base, the Mode button on the front and the Settings button at the rear all at the same time.
Than hold down the Mode button on the front for two seconds to show all zeros. You'll now be able to input your reading by pressing the Mode button on the front which increases the reading. You can set the decimal point position if required by pressing the Start/Stop button. When you have the reading right, press the Set button to lock it in.
Now you put in the wheel diameter again and press Set, then carry on to complete.
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