Wheel Bolts
Remember that every wheel spacer needs a longer wheel bolt or stud. It's amazing how many bolts we sell without spacers so this fact is getting lost on a lot of people (or their supplier is leaving out critical information). The correct length wheel bolt is your stock bolt + the thickness of your spacer. As a general rule, we consider the stock BMW length bolt to be 25mm as measured from the base of the cone seat to the tip, including all threads and shank. So a 10mm spacer will require a 35mm wheel bolt. However, we have seen a range of stock BMW bolt sizes from 25 to 28mm. A bolt that is too long will interfere with other parts inside the hub (ABS sensors, parking brake mechanism, etc). Existing wheel bolt offerings may vary by 2-3mm but you can trust us that we have extensively researched, sold, used, and tested the fitments on all of the spacers and bolts that we sell. If a situation comes up where an unusual application is needed, we have many sizes to offer.