Greetings friends,
This is a continuation of my series of posts documenting the restoration of my BMW R65. For the previous post in this series, click here.
I bought a Brembo brake caliper (sort of) sight unseen on Ebay. The "unseen" portion of this purchase was the condition of the inside of the caliper, as well as no part numbers being provided, only that this caliper was the correct vintage for BMW airheads. For $40, I really couldn't pass on the price and took a chance on it...
When it arrived, I was amazed at how nice the caliper was, and after opening it up I found almost no corrosion or other significant signs of wear! I hit the jackpot but decided the rebuild the caliper anyway, primarily due to the fact that I can only assumer all the seals and gaskets are 40+ years old and need replacement anyway.
Brembo provides a huge selection of repair and rebuild kits for their brakes, and I was pleased to find the exact kits I needed for this specific caliper. The caliper didn't come with the retaining pins and spring for the pads, so I had to buy those separately. The seal kit came with piston gaskets and dust covers as well as replacement bolts for holding the halves of the caliper together. I'll go into more detail below.
Cleaning the interior of the caliper was an easy process, like I said there wasn't much corrosion at all, and the surfaces just had old brake fluid on them. A thorough wiping with acetone and paper towels cleaned them right up. Some acetone-soaked Q-tips were able to reach into the small holes and remove any build-up.
The Brembo kits included some assembly lubricant which was much more viscous than brake fluid but it made the re-assembly a breeze. In a matter of about 15 minutes I installed the piston seals, dust covers, and bolted the two halves of the caliper back together. A small O-ring is sandwiched between the halves of the caliper to connect the brake fluid galleys, so both halves of the caliper receive fluid. When torqueing the big bolts holding the caliper together, I mounted the caliper back onto the forks which gave me the leverage I needed, as the torque spec for these bolts is 50 ft-lb.
The brake pads have alignment pins as well as a retaining spring, which may look a bit clumsy in the photo below, but once around the brake rotor will be aligned well. At this point the reassembly is complete, I just need to reinstall the caliper onto the forks and bleed it with new fluid!
I hope to be able to make more posts soon for this project. Life has been busy and this project has been on the backburner, but I pretty much have most parts in place to at least have the bike moving... just gotta type out a lot more of these updates. Keep an eye out for more posts!
Thanks for reading,
Juju
