Maximum rear wheel bolt protrusion

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Eddie in TO
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Maximum rear wheel bolt protrusion

Post by Eddie in TO »

Does anyone know the maximum length a rear wheel bolt can protrude behind a wheel to avoid touching the parking brake system?

I need to push out my rear wheels due to new wider tires therefore I'm trying to source longer bolts to accommodate the spacer. I prefer to source the right length from the start as opposed to buying new bolts and having to trim millimeters off on all 10 bolts.

Thanks,
Eddie
Eddie Ribeiro
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Mike W.
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Post by Mike W. »

I used to know, but it's not a whole lot, like you said the parking brake parts are in there, unlike the front which can go waaaaay in. But what you can do to measure it is count how many turns the stock bolts go in, 6-6.5 threads IIRC. Remove the wheel, then count how many more before it hits. Then calculate or count threads and length. I want to think it's only 3 or 4 threads, but it was a long time ago I did the test myself.
Mike W.



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Eddie in TO
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Post by Eddie in TO »

I know that 19mm in length behind the wheel works. Anything above that will come down to mm's on whether there will be any impact inside.
I found some bolts locally that are very long. I'll give 21-22mm a try and trim down from there and let you all know. I hope to tackle this within the next few weeks in between home repair activities.
Eddie Ribeiro
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1980 528i with a BMW Motorsport heart

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