Try Bilberry or Autosmart g101 these will lift most dirt without being acidic., or any other non acidic wheel cleaner.
Alternately try some wd40, sounds daft but it works.
If the dirt is ingrained you may need to move to a more aggressive wheel cleaner one that is acidic, i dont like using them
but it will get the dirt out rinse with plenty of water.

Hope this helps.


Kevo

Off shopping tomrrow and Im gona pick up a small hand held steam cleaner, should be ideal for wheels and exhausts as there is not abrasive chemicals just steam. Shouldnt imagin it would do any harm to painted surfaces either factory or after ie your orange wheels.

Thats what mine were like sandpaper all the grit turned in like wet mud is how i think 2 explain it lol. i got most of it off but inside the wheels are still really bad after cleaning them. the face of the wheels are more of just brake dust. its the insides im not happy with. Will never leave my car so dirty again lol. Im not lookin into gettin a cheap 4x4 to use in winter and for work. Im using my abarth everyday and in its a year old now with nearly 18,000 on the clock. So wanna use it as a weekend pride and joy car and the sunny days.

service has been done> but its got go back and shock the passenger suspension sorted as its knocking. Been cleaning the car 4 that. Yes bright orange you can see right inside my wheels

ive always done the inside of my wheels as my arm fits through the wheel

Cquartz IronX is supposed to be quite good and is acid-free and pH balanced. Currently out of stock of the 500ml from Clean your car but you can also get a sample size.

I have noticed how bad they get! Not very easy to clean at all, I use a toothbrush now! Will clay them when summer comes.