Why do wheels need cert?

[dodgeram1]

Why is it you have to cert for wheels? I have many cars with at least two sets of wheels for each as they do not have certs I dont have any problem changing them when I feel like it, and one of my sets is alloy centered steel rims as mentioned by someone else great set of wheels dont knock them. They are old and very well made, my car gets a hard time, no signs of fatuige at all.Common sense says you only fit wheel sizes that clear everything and dont rub.

[Dan]

Wheels don't always require certification:

Aftermarket wheel and tyre fitments don’t require certification if the wheels:
– are a known and reputable brand non-OE item, and
– would be considered an appropriate fitment for the vehicle type by the wheel manufacturer, and
– are not modified, and
– spacers or adaptors are not fitted.
• the tyre tread:
– does not protrude beyond the unmodified original body panels (including unmodified factory-fitted mudguard extensions), or
– protrudes beyond the unmodified original body panels, but is covered by aftermarket or modified mudguard extensions or modified body panels, and the track width has increased by no more than 25 mm from OE.
• the tyres:
– have an outer circumference that is no more than 5% greater than OE, and
– are an appropriate selection for rim width, and
– have tread that does not extend beyond the original or modified body panels or guard extension

Anything outside of this requires certification.

However, if a vehicle has other modifications that require certification then any wheel and tyre change will also be inspected and the details noted on the certification plate, even if it is within the above threshold. In this way the vehicle is certified in its entirety and all components work together as they should.

A change back to standard wheels can cause issues with the other modified components, like rubbing on suspension and brakes, so the fitment is inspected and a test-drive and brake test is conducted. The plate is then replaced with a new one recording all the correct details.

Common sense is great, but I find sometimes people forget they have it.