Front Brake Drag

[Julio A.]

My front brake is dragging. After a short ride around town, the R65 was left on the garage for 3 minutes. Out of curiosity, I touched the Brake Disks. My left hand is now full of Blisters and some skin peeling.

What do you think could be the problem? I did remove the calipers, cleaned the pads and did bleed off some air from the system and topped up fluid this morning.

Gosh, I really learned my lesson today. My left hand stings.  

[Bob_Roller]

Sounds like the small bleed hole in the master cylinder may be clogged, not allowing fluid to return to the master cylinder resevoir after you use the front brake .

[montmil]

Yo, Julio... Do Not put your tongue on the frozen metal flagpole mast. [smiley=ROTFLMAO.gif]

Young and ignorant Texas cowboy visits the local smitty who is shaping a set of shoes for a customer's cow pony.

Dumb cow poke picks up a freshly wrought shoe just barely outta the coals. Quickly drops it.

Smitty says, "Hot, ain't it?"

Poke answers, "Nope. Just don't take me long to look at a horseshoe."

Monte

[nhmaf]

+1 with Bob's suggestion as the most likely/easiest to check location.  Otherwise, you may have:
1) If you have old/original rubber brake lines, a bit of rubber may have come off inside the line and is blocking the return flow /release of pressure within the brake hose, or
2) a bit of rubber/grit or gunk made its way into the caliper and is causing similar problem there in one of the passageways, or
3) the pisotn on the caliper has a ring of rust/crud on it which is preventing it from retracting back into the caliper, causing dragging.

ITems #2 or 3 require teardown and cleanup of the calipers, Item #1 may be solved by replacing brake line hose alone, but if I did that I'd also take the calipers apart to ensure they were OK.

Hopefully it is just some sludge in the TINY return hole inside the M/C reservoir - a bit of congealed brake fluid could plug it up.   Make sure to use NEW clean brake fluid from a sealed can, and flush out all the old fluid while at it.

[Julio A.]

I've ordered new Brake lines - Steel Braided ones.
I'm just waiting for those before I tear open the whole system. i'll also throw in new brake pads with it.

There is a not-so-slight brake fluid leak at my front brake lever. I believe something is really wrong with the brakes. I'm scared that the master cylinder bore is dinged up or something.

I'm opening it tomorrow.

BTW, Anyone watching "the" wedding?  

[Bob_Roller]

Not too uncommon to get some corrosion in the master cylinder bore, if the fluid isn't changed often enough, especially in a humid region such as yours .

[nhmaf]

Just make sure that you get the organic (non-metallic) pads if you've still got the original drilled stainless rotors on the bike (see other recent brake thread for the consequences of using metallic pads)

[Julio A.]

Thanks for the heads up, I was about to install sintered pads.  

[bruce_launceston]

If you do have a blocked fluid return hole in the master cylinder you may not be able to get all the air out of your new brake hoses, hard enough at the best of times with all the loops and bends behind the headlight.
If your master cylinder is leaking backwards it would seem that you will need a piston and seal kit so it is a good opportunity to clear the tiny (0.35mm) fluid return hole.
I have honed the bore of my master cylinder a few times. I use 2000 grit wet and dry sandpaper wrapped around a timber dowel (cut a slot through the dowel to hold the end of the paper, then wrap it around) & make sure you only hone in a circular motion, not lengthways in the bore.

[zebedee]

There is a not-so-slight brake fluid leak at my front brake lever. I believe something is really wrong with the brakes. I'm scared that the master cylinder bore is dinged up or something.

I'm opening it tomorrow.

Very minor corrosion in the master cylinder bore wears the lip on the rear piston seal which in turn leaks out the back of the cylinder and onto the tank, thus many R65s have paint bubbles on the right front corner of the tank.

Stainless steel sleeving is rumoured to fix this problem for good. Having experienced it twice in about 5 years, I had my master cylinder stainless steel sleeved. It took a good 15 years to come back this time; the remaining alloy at the end fo the bore corroded. Any brake place should be able to sleeve it for you.