Bolt length for BBS RA?

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MattyHarris
Posts: 14
Joined: Thu Dec 27, 2012 6:56 pm
Location: Minneapolis, MN

Bolt length for BBS RA?

Post by MattyHarris » Fri Jul 12, 2019 6:41 pm

I have BBS RA wheels to put on the car, 16x7 all around. I've read that these wheels require longer bolts, but I haven't found anything definitive on which length to buy. Anyone know? thanks
1980 528i 5-speed
1994 530iT

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maybeillbuyit
Posts: 189
Joined: Mon Feb 17, 2014 12:26 am
Location: Vancouver BC

Re: Bolt length for BBS RA?

Post by maybeillbuyit » Sun Jul 14, 2019 11:12 am

I just put a staggered set of RAs on my 530i. 7x16,8x16 I bought these bolts after seeing online somewhere this was the size to get.

I also measured the amount the stock bolt protruded from the stock wheel and then tried to make sure the new bolts stuck out the same. The 45 mm bolt was a little long but I went with them. During installation the bolts were hitting on something in the parking braking brake of the rear rotors. So I ground about 3mm off the back bolts making sure to cool the bolt in water every few seconds of grinding to avoid weakening the bolt. The 45mm worked fine in the front. I also see theres a 39mm bolt on Amazon. That may be a better choice if you don't want to have to grind. My car and wheels aren't here right now so I can't verify If a 39mm bolt would be long enough. The other thing is these are chinese made bolts, not sure I'd do it again. I'd consider going with a higher quality product next time.
ImageIeJdJGrnTeCbpho9rXTYqA_thumb_1ec2 by Dave Grayson, on Flickr
1977 530i another project
1979 635csi Euro "project"
1987 635csi

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Mike W.
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Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: Bolt length for BBS RA?

Post by Mike W. » Sun Jul 14, 2019 1:18 pm

I don't know what size is needed, but you want a minimum of 6 threads engaged. Too long isn't a problem in front but will be in back if it hits the e brake parts.

Ebay is another source but even more likely to be questionable quality.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter

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