front brake sticking?

thielb

thielb

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the front brake always squeals when i use it. not a big deal it happens. my brand new brakes on the car squeal a little. whats getting me is when i try to walk my bike backwards, its hard as all hell and the front break squeals ever so slightly like there's still contact with the rotor. possible that the front brake just sticks a bit? can i adjust that so shes not such a b*tch to walk around in the garage? may be a dumb question, i dont know, just looking for some help thanks guys
 
I don't know about your brake grabbing when you are not pulling the handle, but a mechanic friend of mine said that good disc brakes working properly squeal.
He says that car companies have turned themselves inside out trying to mask/minimize/cancel squealing because customers ignore facts, complain about squealing and insist that dealers make it stop.
Again, according to him, some of the hoops they have gone through to stop the squealing customers actually may reduce the effectiveness of their disc brakes.
But, "the customer is always right" (right?) and if customers want longer :yikes: but quieter stopping distances, that is what they are given.

An old mechanics' wives' tale? I don't know. But squealing doesn't bother me any more. :shrug:

As to the difficulty in pushing your bike backwards - any chance that one of your wheel bearings is starting to go?
 
i kinda doubt it. theres barely any miles on my bike. i dont mind the squeal much either when im actually braking. the fact that theres brake squeal when im not pulling the brake lever is whats tickin me off. front brakes must not be fully disengaging? any way to ensure that it fully disengages?
 
Get the front tire off the ground and try spinning it. It should spin easily. If not, the slider pins may be sticking, the caliper piston is sticking, or the brake lever has been adjusted incorrectly.
 
You'd have to take the caliper off and determine where the problem is. When you have it apart, you should be able to push the piston in by hand and the sliders should move freely.

Let us know what you find.
 
Disc brakes are self-cleaning and adjusting for the most part. They should drag just a tiny bit, just so when you've left the bike for a few weeks and there's some rust on it, it cleans itself off. Completely disengaging is bad.

On the other hand, your wheel should turn very easily and you shouldn't be braking when you're not pulling the lever. It's a delicate balance.
 
It sounds like you have either a sticky caliper, or a clogged master cylinder.

I had this problem on the rear brake of my XS. The brake hose deteriorated and rubber crumbs plugged the tiny hole in the master cylinder, so it wouldn't release for a while.

A caliper can also stick because of corrosion and dirt on the piston. The OE pistons are made of soft steel and chromed, and someone trying to remove a stuck piston with a vise grip will quickly mess it up. A scratch through the surface plating will make it rust and that will make it stick, too. Fortunately, you can buy a replacement made of much better stainless steel. I got mine from HVC Cycles.

So, what color is your brake fluid, and how old is your brake hose? If the fluid is black or brown and the hose is marked as being made in 1977-1982, I'd say you need a new hose and a good cleaning of the master cylinder.
 
When I first got my bike my front brakes were doing more than sticking,they were locking up completely.Hence I had my first drop over when they locked up on the dirt road heading into my place.Ripped a little meat off both knees(ouch) now I built my caliper and try bleeding the system which the advice I offer to remedy your problem.Maybe do a complete front caliper rebuild.Trust me you dont want those front brakes locking up while you are riding unless you got a good piece of body amor.
 
well i got the front end up. with a good push it barely gets around twice. to push it backwards i actually have to muscle it just to get it to move and the brake grinds something fierce. thoughts?
 
Had same problem with mine. Check out thread "brakes are stuck" . In my case it was a problem with the master cylinder. There is a very small hole in the m/c that allows the fluid to flow from the the bore back into the reservoir when the brake lever is released. With this hole blocked the system will stay pressurized even after the handle is released. Mine started the same as yours, only dragging when rolling backwards (hole partially blocked) then got to the point of full lock up when riding (hole fully blocked) . Could not get hole cleaned out properly so I ended up replacing m/c and pads due to glazing (over heated)
 
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Sounds like a good thing to do as a preventative measure in case yours is the same as Ken's. Yours hasn't progressed to glazing and so you shouldn't need to replace and rebuild if you can correct it now.
I've never done disc brakes before, but most people advise replacing the fluid every so often. Since there is so little of it, it would seem to be a good idea while you are poking in that hole. Read Ken's thread though to make sure you don't poke with something too hard. You don't want accidentally to change that hole, just make sure it's open.
 
fluid looks clean and at the right level but it couldnt hurt to change while i have the MC open i suppose. poking in that hole and flushing some fluid is my plan for now i spose. if that doesnt do anything, ill be looking for some more advice. thanks for the help so far and i bet ill be seeking some more real soon :doh:
 
If available, you might be able to try squeeze fluid from the bleeder screw on the caliper, possibly dislodging any crud in the master cylinder. A big syringe might be able to do it.

Also, I would definitely first pull the front caliper off and make sure none of the pads are sticking. Since it spins reasonably well in the forward direction, I'd like to think that the MC is retracting the pistons at least somewhat. Get some high temp brake grease and clean/grease up the sides by the spring holders around the edges of the pads, make sure they move freely. Worth a shot, and definitely easier than dealing with the master cylinder!
 
Read the manual, then remove the caliper and check the sliders and the piston. Sounds to me like a slider or the piston is seized, or both. Make sure to check that the hole on the hollow slider isn't plugged, or the brakes will drag once you have it back together.

And remember, your life and possibly someone else's life depends on your brakes working properly. Before you ride the bike, pretend someone has a gun to your head and will pull the trigger if any fault is found with the brakes. :gun: If you don't feel nervous, you are overconfident and should get a pro to double check everything you touched. Once you are confident with your work and have triple checked everything, go for a test ride and ride like Lou Ranger. :D Gently test the brakes a few times before attempting any sort of speed, they will feel very different than you are used to.
 
Don't worry, it's pretty straight forward, it's just like changing brake pads, it all just kind of fits. Unbolt the big caliper bolts, pull it off (suspend the caliper from your handle bars with some string to keep the weight off the brake lines) and go at it.

If you end up finding that you need to replace the pistons, then you're getting into territory I haven't been (and really hope I never need to).

If you have some time, watch a couple youtube videos on replacing brake pads. Even videos for cars should give you a general idea of what you'll be doing.
 
how old is your brake line? There should be a manufacture date stamped into it somewhere. You might want to replace it right away as well, yamaha recommends to replace them every 4 years, but everyone forgets/neglects to do this.
 

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