Well, tastes differ, but I prefer something other than black powdercoated wheels on a Touring model. The front wheel looks like a big balloon. On a fully blacked-out Roadster, perhaps, but the Touring needs bling.
The wheels are essentially untreated aluminium, except the inside of the spokes and parts on the hub which have some kind of silvery coating (I'm guessing powdercoat).
How to polish aluminium isn't a secret, there are numerous guides on the interwebs. The big issue is access. The humongous brake disc in the rear makes getting at the wheel to polish it almost impossible. Last winter I put the bike on the lift and just removed the wheel, removed the disc and went to town on it.
Started with 800 grit wet sanding, then 1200, then 2000 and the final step was a machine polish with Flitz metal polish. I used a drill, and rotary polishing wheels of various sizes.
It's lasted fine, though it's slowly dulling again - aluminium oxidizes instantly which forms a protective layer that keeps the shine for a while. But it did take a few days to do, which was fine since it wasn't riding weather anyway. But I don't see any realistic way of getting the entire wheel shiny except dismantling it to this point to get access. You can do it solo assuming you have a hydraulic lift and some kind of lift adapter so the bike stays on the lift even though you detach a wheel.
There is a whitewall under the tape. The result was also not 100% perfect, but I was still pleased with the end result.
If you're not keen on doing this once a year or so, there are other treatments besides black powdercoat. I'd choose a "chrome" powdercoat first personally, even though it doesn't really look chrome, more like a bright silver. I'm also intrigued by a process I've seen only on a web site thus far,
CalChrome Clear - CalChrome.com