I am looking into this too.
The products I have found that say they are save with Alum Wheels are
1Z Einszett Wheel Cleaner “Feigen Reiniger”
Types of Wheels
Having a set of clean stylish wheels has been a top priority lately. Wheels on the market today are made from a variety of metals including forged and billet aluminum, cast metal, and finished chrome. Knowing what your wheels are made of is the first step to properly maintaining them.
Chemical Guys WHEEL AND RIM CLEANER-PREMIUM BLUE
Premium Blue unlike many alternative products dissolves grime and brake dust without damaging your chrome and alloy wheels and rims. It's a highly effective wheel cleaner that can also double up as a high quality degreaser to safely remove brake dust, oxidization, dirt oil and grime. Made from a unique non Hydrofluoric Acid formula.
Duragloss #821 AWC (All Wheel Cleaner)
s formulated to clean all wheels. Removes brake dust, road film, oil and grease. Safe to use on all types of wheels including clear coated, painted and highly polished.
Pinnacle Gel Wheel Cleaner
Safe enough for all wheels, including aluminum, painted, polished, anodized, and clear coated! Safe to use on sensitive billet wheels.
Wolfgang Tire & Wheel Cleaner
Rest assured that Wolfgang Tire & Wheel Cleaner is safe to use on all kinds of wheels—including aluminum, painted, polished, anodized, clear coated and billet wheels.
Griot's Garage Wheel Cleaner
Griot's Garage Wheel Cleaner is made from premium biodegradable ingredients and is safe for all types of wheels.
Simple Green PRO M
Simple Green Pro M removes fingerprints, water spots, streaks, and food & grease marks from metal surfaces including aluminum, chrome, brass, stainless steel, and more.
I have used the regular Simple Green on my painted rims and it work great but it marks alum.