Rear caliper bolts

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mark99

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Caliper bolts
Is there a source for the rear caliper bolts? the bolts that hold the 2 haves together, with vented disks (have the spacers)
I ordered the front bolts from WN and at least at that time they didn't have the rears, even if they did now I would like to avoid the flat rate shipping cost and time
Thanks
 
mark99 said:
Caliper bolts
Is there a source for the rear caliper bolts? the bolts that hold the 2 haves together, with vented disks (have the spacers)
I ordered the front bolts from WN and at least at that time they didn't have the rears, even if they did now I would like to avoid the flat rate shipping cost and time
Thanks
Click to expand...

Mark,

If you come up dry, I have a spare set of rear calipers. They are still hooked up to the whole rear axle assembly. I likely won’t be able to set them free until tomorrow. Figure $14 flat rate and you would have by Saturday. Ideally, if someone has the bolts or calipers handy that would be the way to go.

I searched for front bolts this week. I even mailed AAA Metric (The place in Denver that I mentioned). Few places car M7x55mm (presumably smaller in the rear). M7 button head socket screws - black oxide in 10.9 or 12.9 are very difficult to come by!

Good to know about w&n!
 
Hi Mark,
I will tentatively say I will get them from you, will let you know
Did you figure out he brackets with all metals?
 
mark99 said:
Hi Mark,
I will tentatively say I will get them from you, will let you know
Did you figure out he brackets with all metals?
Click to expand...

No I haven’t had a chance to ring them. I’ll take that one offline.
 
Hi Mark
https://www.classicbmwparts.nl/ have these bolts, but they are M6, slightly smaller (0,35mm)diameter than the original 1/4" bolts on our rear calipers. I was surprised when I received the new bolts since I was not aware that the originals are inches. The extra space around the bolt is noticeable and my first impression was that it was the wrong bolts. I wrote to classicbmwparts about the issue and they replied that they use the M6 bolt when the refurbish calipers and it is no problem with regards to strength.
They may be right but I would like to have other members view on this before I use them.
They located i Netherlands, so shipping cost is unavoidable (as for W&N). (Remember to buy nuts)

Henrik
 
The original bolts are called "ribe " bolts and any brand of car that uses ATE calipers use them, Alfa, Porsche and of course BMW I have looked and looked for these but have not yet found a source for them Belmetric sells a 12.9 Allen head black oxide 7mm X 30mm It appears that they only have the one size McMaster Carr has a bigger selection of the same style bolts Make sure whatever bolts you get, you also get 12.9 nuts as well
 
Oh man I know this problem, it took me forever to find the correct length m7 socket head screws when rebuilding my rear l calipers (there are two different lengths needed).
Fronts were easy, I also got mine from Wallothnesh.
I eventually got lucky and found some m7 hardware from tola-tools.de but only in one length and I had to wait ages for them to arrive. They are a few mm longer than original but better than a few mm short which you usually see.. the other length I will have to look up where I got them from.

4B1353DA-44EA-428E-B200-1809FB72530B.jpeg


99395127-BF16-4AB2-938E-06A8E70953BC.jpeg
 
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Henrik said:
Hi Mark
https://www.classicbmwparts.nl/ have these bolts, but they are M6, slightly smaller (0,35mm)diameter than the original 1/4" bolts on our rear calipers. I was surprised when I received the new bolts since I was not aware that the originals are inches. The extra space around the bolt is noticeable and my first impression was that it was the wrong bolts. I wrote to classicbmwparts about the issue and they replied that they use the M6 bolt when the refurbish calipers and it is no problem with regards to strength.
They may be right but I would like to have other members view on this before I use them.
They located i Netherlands, so shipping cost is unavoidable (as for W&N). (Remember to buy nuts)

Henrik
Click to expand...

I wish they were M6. You can buy black oxide button head M6 socket screws on Amazon, up to 50mm. They are 10.9 though. M7 is infinitely more difficult to find. Everyone else besides classicbmwparts seems to think that they re M7

Disclaimer, these are M6...
 
Henrik said:
Hi Mark
https://www.classicbmwparts.nl/ have these bolts, but they are M6, slightly smaller (0,35mm)diameter than the original 1/4" bolts on our rear calipers. I was surprised when I received the new bolts since I was not aware that the originals are inches. The extra space around the bolt is noticeable and my first impression was that it was the wrong bolts. I wrote to classicbmwparts about the issue and they replied that they use the M6 bolt when the refurbish calipers and it is no problem with regards to strength.
They may be right but I would like to have other members view on this before I use them.
They located i Netherlands, so shipping cost is unavoidable (as for W&N). (Remember to buy nuts)

Henrik
Click to expand...
thanks!

On their website, they have listed the following, I sounds like you get 1 bolt, so I suppose one needs to order 8 of those?
And each is the same length?

Bolt for ventilated caliper rear (M6 x 65, Repro)


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FWIW, I had mine replated with the black oxide zinc process but also had them baked afterwards to avoid the hydrogen embrittlement phenomenon. I would think most plating houses have the ability to do this as it is a well-known phenomenon in that industry. This is mostly a concern with high tensile strength grades (as in these bolts: 10.9 and 12.9), not with the more common 8.8 rating. I did this 4.5 years and 14,000 miles ago and the bolts haven't yet snapped...

I also distinctly recall either a post by Eric from PBM on this forum stating they re-use them, or a private email communication I had with him.

P1100178.JPG


P1100179.JPG
 
Interesting how the 1/4" grade 8 bolts compare in tensile strength to the10.9 and 12.9 6mm bolts.

Proof load of a M6 1.0 10.9 bolt is 3754#
Proof load of a M6 1.0 12.9 bolt is 4384#.
Proof load of a 1/4-28 Grade 8 bolt is 4350#

Readily available here:

 
someone said there are 2 different lengths for the rear calipers
The bolts at ClassicBMWParts.nl for the rears seem to be offered in one length, 65
1/4 inch is 6.35 mm so less than 7 but larger than the 6M sold at ClassicBMWParts.nl
so I might try the 1/4 as suggested by Mike
 
You can go to your local hardware store and buy a 1/4" bolt to see if they fit before you pull the trigger on the more expensive ones.
 
well 1/4 would have to fit, I measured the hole at .267 inch, about 6.79mm
but I will try a 1/4
I ordered the bolts
and they are cheap, I have been buying 2 or 3 at a time from the hardware store, those are expensive
 
mark99 said:
someone said there are 2 different lengths for the rear calipers
The bolts at ClassicBMWParts.nl for the rears seem to be offered in one length, 65
1/4 inch is 6.35 mm so less than 7 but larger than the 6M sold at ClassicBMWParts.nl
so I might try the 1/4 as suggested by Mike
Click to expand...

That was me, 6 posts ago.. The inner and outer are different lengths.
The bolts you need are M7 x 55mm and 65mm.
 
JamesE30 said:
That was me, 6 posts ago.. The inner and outer are different lengths.
The bolts you need are M7 x 55mm and 65mm.
Click to expand...
right, but the 1/4 inch only come in 1/4 inch length increments, I don't think a tad too long would be a problem (?)
I ordered 8 each of 2.5 and 2.75, they have a $15 minimum order anyway
 
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