I also have spoke rims on my HD FXDX Sport Dyna. They are the traditional chrome rims with a tight arrangement of spokes very close together. Similar to most spoke rims of motorcycles.
A real PINTA to clean.
My Dyna is 1999> 20 years old and I have never worked to much on them maybe once a season it gets a good bath and I spend about 15 minutes doing both rims.
I little never dull and they shine right up.
But the Ducati rims are matt black and the spokes are very far apart. No Chrome
so simple power washer cleaning should handle the job well.