Brake Caliper leaking

Right front brake caliper on my 83 Midnight maxim seems to be leaking. The bike has less than 11k on it.

Question 1.. Should just rebuilding the caliper fix this problem. I have not pulled it off yet to inspect. I am hoping that a rebuild will do it.

The PO said he rebuilt one of them. The brakes have never been great. The fluid is super clean. He must have at least flushed it. I have a list of parts that I am going to check with Chacal about.

Question 2... In the event the caliper is bad, does anyone have a good used one? I can not swing buying new one at this point.

Thanks,
Mike

 

It's kinda hard to fudge up the body of a brake caliper... Unless someone stripped the bleeder valve or the banjo fitting threads. If that's not the case, you should be able to rebuild it.

You'll have to take the caliper apart to see what's salvageable and what's not. In particular, you have to check the piston surface for scoring or heavy rust. Sometimes just buffing it with a polishing wheel and some rouge will smooth it out enough, but sometimes it just has to be replaced. You might also get a rebuild kit (2 o-rings) and a new bleeder valve. If the banjo bolt still looks ok, just replace the two copper crush washers.

Old brake fluid has a tendency to turn into something like dried mud (right after it turns into gelatinous goo)... you will have to scrape it out of the grooves where the o-rings go, otherwise the new ones will not seat properly. When you put the piston back in, lubricate the o-rings with some brake fluid.

 

It's not likely that the Caliper itself is bad. It's made of aluminum!

On a bike that sits the Caliper Piston Seals get brittle and rot; then leak.

Caliper Seals are easy to replace. They fit into channeled grooves on the Inside Diameter of the Caliper Piston Bore.

As Stereo mentioned ... getting the grooves cleaned completely out of any foreign matter is key when doing a Caliper Seal job.

The stuff that forms in the channels can be nasty to scrape out of there, but you have to remove it all right doen to bare aluminum or the Seals oval-out and make the Caliper Piston stick.

I took a piece of an old CB Radio antenna and heated the end
Bent it over at a right angle after flattening it out to make the scraper end
Then, with a little bit of grinding ... I had a scraping tool that fit in there perfect.

The idea is scrape the channels clean and NOT scratch them!
The rubber seals make a tight fit and you don't want the grooves scratched-up allowing brake fluid to seep past the seals.

 

Well that makes me feel a little better. I need to order the stuff from Chacal.

Do you suggest doing both sides even though the other side is not leaking yet?

 

Given the age of your bike, you should rebuild the entire system. New lines, both calipers and master cylinder should be overhauled and new rubber installed. It is not cheap (about $250 for the whole kit, check with Chacal) but what is your hide worth? All of my bikes are being rebuilt as we speak because of age rot that has claimed the performance of my brake systems. Remember, you want the brakes to work correctly, each time, every time.

 

I plan on doing the whole thing. I want the SS brake lines. I was a little hesitant at first. But I plan on keeping this one for a while. I guess a little green here and there is better than a monthly payment. I do have my eye on a few newer bikes. I like the Yamaha FJR and the Honda 1300ST Both with ABS. Any thoughts on ABS?

Mike

 

ABS is fine for cars, I personally am old-school enough to want to be in 100% control especially on a bike. Lots of folks block off the 750 Seca anti-dive I assume for the same reason. Guzzi or somebody had a "one-pedal applies both brakes for you" system a few years back, it was less than effective. Check out the EBC website for aftermarket rotors, about 1/3 the cost of OE Yam and way cooler (literally and figuratively) and I believe Chacal sells 'em! SS brake lines a good idea too, the Yamaha lines have always been a bit "squooshy" for my liking---when I grab a handful of the Lockheed on my Nort, it's like grabbing a rock. I'm planning EBC rotors/SS brake lines retrofit on my 550 over the winter.

 

Chacal may also have SS brake lines for your model. I hooked up with all the parts for a total rebuild (less rotors, but that will change shortly) for about $250 (Seca 750, loads of fun) if you include the new SS lines. I cannot stress enough how important it is to have good brakes. No room or margin for error when it comes to stopping so best get it right the first time.

 

I sent my order in. I am doing the SS lines. Rotors seem fine.

On the topic of ABS the salesman at the store said they are good in the rain. He also said the stopping distance is greater when dry. I am on the fence. It will be some time before I can afford a new bike anyway. Just wanted to start getting some opinions. I can see the point of being in complete control of what the breaks do. In a car you have 4 wheels to stablize you. I would wonder how the brakes react with only having 2 wheels. Maybe once I have good brakes on this bike I will change my mind about ABS and scrap that all together.

I have been reading so much on here. There is such a wealth of knowledge here. Everyone gives great advice. I hope to be able to add to the knowledge base as time progresses with my expirience.

Have a great day!

Mike

 

ABS would be a benefit in that it will not allow the wheels to lock up no matter how hard you grab the brake. The point you want to be at in a braking situation is where you have maximum traction and still have the ability to steer. A sliding (locked) wheel doesn't do so well in the steering department.