Brembo Brake Caliper Halves Bolt Torque

[88bmwjeff]

I rebuilt the Brembo calipers on my 1988 R100 RT. To cut to the chase, what should be the appropriate torque setting for the two bolts clamping the halves together.

Here’s what I’ve found so far….

I read through the included Brembo instructions and if I’m reading it right (they're not that clear), the two bolts clamping the two halves should be tightened to 50 nm or ±36.9 ft lb. This is not my area of expertise, but that seems high for an 8.8 M10 bolt that has a torque setting range of 25-39 nm to 18-29 ft lbs, according to Clymers. Snowbum’s sight indicates torque settings for the Brembo calipers with four bolts, but doesn’t seem to reference the older Brembo calipers with only two bolts. Brook Reams references the torque settings for the inner bolts indicated on Snowbum’s site. I have a repair manual for the airhead GS, and BMW doesn’t specify a different torque setting other than normal for the bolt type.

 

[20774]

Seems like this has been discussed before. Check the threads in the similar threads pane at the bottom of the screen.

 

[88bmwjeff]

Thanks Kurt, but none of the previous threads/posts talk about the torque value for the bolts that clamp the two halves together.

 

[20774]

Maybe google site search?

site:forums.bmwmoa.org brembo torque

 

[pauls1150]

Maybe the factory bolts are a stronger-than-typical steel, considering what they have to do...?

 

[98lee]

Generic bolt torque specs. assume that they are being screwed into the same material as the bolt. When screwing into something softer (aluminum caliper) you need to take that into consideration (lower torque). More thread engagement (more than 1.5 x diameter of bolt) allows the torque to be raised a bit.

The weak link is not the bolt, it is the aluminum threads in the caliper.

Still can not give you an exact spec. even though your bike uses the exact same Brembo calipers as an early Flying Brick (K75-K100). I’ve checked the BMW factory Manual, the Clymers, and the Haynes manuals, but no listing.

The only torque listing that I found was in a Harley manual. It said “tighten until it breaks, then back off 1/4 turn.”

 

[88bmwjeff]

Thanks everyone. I've decided to go with 22 ft/lbs, since the few places I've seen 22 ft/lbs stated, none have indicated leaks.

 

[kbasa]

Thanks everyone. I've decided to go with 22 ft/lbs, since the few places I've seen 22 ft/lbs stated, none have indicated leaks.

I'm late, but that's what I used on my 84 R100CS. I think 44ft lbs. on the mounting bolts? EDIT: It's 24 ft. lbs.

 

[88bmwjeff]

I'm late, but that's what I used on my 84 R100CS. I think 44ft lbs. on the mounting bolts?

Thanks. Just so no one accidentally uses 44ft lbs on the mounting bolts, the owner's manual indicates 24ft lbs.

 

[kbasa]

Thanks. Just so no one accidentally uses 44ft lbs on the mounting bolts, the owner's manual indicates 24ft lbs.

Thanks! I'm gonna go back and edit that so nobody is buying a new fork leg or anything.