Style 108 Restoration With a Few Questions

[MSGGrunt]

I picked up a set of Style 108 wheels to have professionally refinished. The set presently on my Z4 is pristine, this will be a second set. I am considering a satin black powder coat to go with the rest of the blacked-out trim on the car even though I have seen black on these wheels and their details tend to get lost in the black color. I am not a fan of black centers with polished lips. Another option I have considered is a dark charcoal grey.

I have heard nightmare stories about bolts breaking while separating the center sections, but I didn't use any penetrating oil or heat and they all broke free without a single one breaking.

Questions:
#1 As shown, one is cracked. Can this be welded? If so, is this as good as a replacement? These are not always easy to find here in the US, and I don't need a whole set. I found a set that are damaged, but one of the 8.5" is in good condition, which is the one I need. The damaged set is 4 hours away and $400.00.

#2 Anything the bolts can be soaked in to "clean" off the blue Loctite and corrosion?

#3 If replacing the bolts has anyone substituted stainless steel instead of titanium?

#4 Are these BBS wheels? I only ask as the center star sections are cast BBS, but the barrels are cast Ronal. I thought Ronal was a wheel manufacturer unto itself?

 

[Zedebee]

You can get the crack welded, which might be fine for you, but you’re unlikely to ever sell the wheel/set for a decent price in the future. A replacement barrel is the answer, but $400 seems a lot to pay. You can get a full set of 108s in good condition in the UK for about £400.

The titanium bolts shouldn’t corrode, more likely they will have aluminium corrosion on them from the centres. The loctite might come off with some nitromors (paint remover) or caustic soda.

I believe the bolts are titanium because steel reacts with aluminium to cause galvanic corrosion, which you want to avoid. The bolts are readily available, so best to stick with them.

I have split several sets of these and never noticed a Ronal barrel. I thought they were all BBS. BMW often used several suppliers for parts, so it may be a US peculiarity.

You were lucky not to break any of the bolts. I hope the refurb goes well.

 

[MSGGrunt]

A set here in the US in good condition is going to cost around $1,200.00 to $1,500.00 US. A refinished set can be as much as $2,000.00 US.

And the first estimate I got to strip, ensure the wheels are true and power coat them was $2,000.00.

 

[Astonyeah]

You can get a full set of 108s in good condition in the UK for about £400.

My 108s are very very poor condition, need a full refurbishment but probably replacement. I’m not wedded to the 108s, but that seems cheap! Do you have any recs of where I can either get new wheels or refurbishing please?

 

[munchkincoupe]

Keep an eye on facebook marketplace for sets that have already been done. There are normally lots if sets on there in various states but you just need to jump on a good set when they come up

Marketplace

 

[munchkincoupe]

A set here in the US in good condition is going to cost around $1,200.00 to $1,500.00 US. A refinished set can be as much as $2,000.00 US.

And the first estimate I got to strip, ensure the wheels are true and power coat them was $2,000.00.

sets here in the UK are much cheaper - would it be worth trying to get one wheel shipped over?

Marketplace

 

[raymond.harper]

You can pick up a set of 108s in the UK needing restoration for £140. Shipping would wipe out any savings, especially when the "big beautiful tariffs" have to be added. Do not use stainless steel bolts; they are weaker than titanium. It took me hours to drill the heads off the titanium bolts that were seized in the hub, so I know how strong they are.

 

[MSGGrunt]

The set of 4 for $400.00 is probably the way I will go. If the Pirelli tires are any good, I will sell those to recoup some of the cost. And I will have plenty of extra titanium bolts to help others out when they find themselves with some that break during disassembly.

I wonder why these are much less expensive in the UK? Were more Z4s sold with them? Or are you folks just a bit wiser and don't want to be bothered with the added complications of a two-piece wheel when it comes to restoring them?

 

[Zedebee]

The UK climate is not conducive to keeping 108’s nice for long. It was one of the most popular cost options, unsurprisingly as it was a really nice wheel. However, other styles have become more popular for the E85, particularly 107s. Being two-piece, they are also considerably more expensive to refurbish properly than one-piece wheels, with the added difficulty of splitting them. That said, most second hand wheelsets are pretty cheap in the UK, not just 108s.

108s were originally offered with a polished aluminium rim, however they were redesigned later in life with a silver painted rim, probably because of the amount of corrosion-related warranty claims.

 

[MSGGrunt]

Funny how taste vary from person to person. I looked up the 107 and not my liking. I have always been drawn to simple 5-star designs like the 108s, Mercedes Penta, and older Bobets or even throwing stars. I had the throwing stars on my 1987 M6 and I bet these would look good on the Z cars, if you could find reproductions with the correct backspacing.