Koch Chemie MWC Magic Wheel Cleaner is an acid-free wheel cleaner you spray on ready to use. It dissolves brake dust and iron particles and turns red where it reacts with iron, so you can see it working. With a pH of 5.5 it is acid-free and therefore safe on painted, chromed and steel wheels. You will find Koch Chemie MWC Magic Wheel Cleaner in the shop.
What MWC does
Wheels are full of abrasive brake dust and baked-on iron particles you cannot remove with a normal shampoo and certainly do not want on your paint. That brake dust is hot when it lands on the wheel and bites in; leave it and it eventually attacks the wheel's paint and the wheels start to feel rough. MWC softens that dirt and converts the iron particles into a soluble form you rinse away. The striking red discolouration you see is the reaction with iron: where it turns red, brake dust is coming loose, so you see exactly where the worst soiling is. Koch Chemie states the formula clings to the wheel and does not dry out, even after a longer dwell, so it works on the vertical surfaces and in the barrels too.
Acid-free and ready to use
Acidic wheel cleaners work fast but are risky: they can attack delicate wheels and coatings. MWC is acid-free, with a pH of 5.5, and therefore a lot milder. Because it is acid-free, it is also suitable for coated wheels. You do not need to dilute it: you use it neat from the bottle. If you want to understand the difference between acidic and acid-free cleaners, read the guide cleaning wheels without damage.
How to use it
Cool wheel. Work on a cool wheel in the shade, not in direct sun or on a hot wheel right after driving.
Spray on. Shake the bottle briefly, spray MWC generously onto the wheel face and into the barrels.
Let it dwell. Let it dwell 2 to 4 minutes, a little longer on heavy dirt; the red discolouration shows where it reacts with iron.
Agitate and rinse. Work the spokes with a dedicated wheel brush and then rinse the wheel thoroughly with a pressure washer.
Tips for the best result
Use a dedicated wheel brush and wash mitt, kept separate from the rest of the car.
Do not let the product dry; work wheel by wheel so you rinse in time.
Rinse the barrels and back well, that is where most brake dust collects.
Test an unfamiliar or polished wheel on an inconspicuous spot first.
You will find more wheel cleaners in the wheel cleaners category.