Are the inside beads of the 5BW wheels finished/clear coated?

[Merlette]

Has anyone noticed if the insides of the OEM 5BW wheels (especially the inner bead) are finished/clear coated?

I think this is a pretty common practice, but with high horsepower cars I wonder if clocking is a concern, so the inner beads are actually unfinished or textured in some way. I wouldn’t want to screw that up if I ever got them refinished or I would ensure any replacement wheel follows suit.

Thanks for any insights…

 

[jbawden]

I replaced a rear wheel and it was more overspray than either a factory effort to paint or avoid painting the rim. I think it's generally recommended not to finish the bead surface both because of the tire spinning on the rim and the added powder coat thickness can make mounting tires a bit harder (at least that is what is true in the motorcycle world).

 

[Merlette]

My V2 wheels are like that too--unfinished on the insides. When I got them PVD black chromed, they left the insides unfinished as well.

I made an inquiry to a different outfit that does wheels on a core exchange basis and they said they refinish the entire wheel, except for the hub mating surface and the lug nut seats. When I expressed concern and asked if the OEM wheels were the same way, they went and inspected a set of Satin Graphite they had on hand and said they were finished inside and out. My wheels will be the base polished/dark android, so not apples to apples...

I don't know why I do this to myself, my car isn't even built yet and I'm already being seduced by the sirens of mod hell

 

[jbawden]

If they are painting, probably not a big deal but it's not that hard to protect the bead from getting powder coated.

Found this picture on eBay of a 5BW. Still looks like overspray to me.

 

[Merlette]

Thanks. They appear and I presume them to be powder coated. With powder coating, you leave the surfaces you want finished exposed and protect the rest. Apparently the heat fusion process doesn't create a lip that would be prone to lifting or chipping during the tire mounting process.

The PVD process is similar to powder coating, but a layer of sputtered metal is applied before the top protective clear coat. Every video I've seen of this process involved priming, powder coating, and sputtering the entire wheel, inside and out, ostensibly to avoid creating a possible way for moisture to wick in or create chip/lift points. Whether the entire wheel is clear coated was ambiguous.

If fully clear coated, suggestions I've come across include roughing up the clear coat on the horizontal bead channels and using alcohol (dries clean) or hair spray (dries tacky) instead of other lubricants to help mount the tire.

Eh, shelving the idea for now...