Motorcycle Repairs and Oil Seals

How deeply is it scored? I assume you are talking about the aluminum case.

If it is a scratch, then it is probably okay. Anything deeper may be an issue that needs replacement, but generally, those castings are pretty thick.

You can't fix a casting by filling a groove. Internal hydraulic pressure will simply split the caliper wide open and you will have a catastrophic brake failure (i.e., brown trousers time).

Have the caliper looked at by a dealer's service company and let them tell you what to do. Your life rides on your brakes. Don't guess when it comes to safety equipment and don't hit my car.

I think that I may have misunderstood where the score is. It sounds like the seal's mating surface is where the damage is.

There are varius sealing comounds made for this. Try an automotive shop. A silicon seal might work, but there are many different types, so ask at the store or even your local service shop what they recommend.

Hi.

What were you using to clean the gallery and are you able to feel the score with your finger? If you can feel it, fluid will pass through.

In most instances you will get fluid passing via the gouge and as you apply the brake pedal you will have minimal response in braking. Eventuyally fluid seepage will end up on your disc and other areas.

Honing the gallery and a resized seal would be the only fix depending on the severity of the score. This would provide resistance for the fluid to stay behind the seal allowing the caliper piston to initate the brake pad and stop you.

If you are not adept at mechanics get a qualified mc mechanic to do it. Your brakes are your life.

Hope this helps.

GA sir.

As a side note. Did you ever try to smooth out a small cylinder? Too small for the hone you have.

I have used a cotter pin with success. Choose the grade of sand paper or cloth for the job. Cut 2 strips to the same hight as the cylinder, and long enough to be too wide for the diameter of the cylinder. Put the 2 strips back to back, and open the cotter pin up to allow the strips to fit in between. Keep the ends even, squeeze the cotter pin back closed and insert into a variable speed drill.

I actually have done that trick in a pinch, it works pretty good.

In my shop here I keep a cabinet packed full of stuff just like that ... but from McMaster-Carr.

What I tend to do on the real small stuff is to use Dremel mini tools.

I didn't include it in my original response to Techracer but when I go through the brakes on my bike every couple of years I use a little piece of the purple Scotchbite scrub pad. I just wet a tiny piece of pad in brake fluid and lightly run around the inside of the bore then flush it. Been doing it for many years.

The drains here are not that good. Flushing calipers seems to clog them.

I do like Scotch Bright better also.