[muaymendez1]

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I have not posted in a while because I ni longer own a wing.I'm hoping someone here knows what can be happening to my brakes,.System has been flushed and checked for movement of calipers but I still need to squeeze uncomfortably hard to get the bike to stop,.
This is ok when I furst go out and my body is fresh,but later in the day with a lil fatiuge I almostt stop using the front brake due to how uncomfortable it is.
The bike in question is a 96 yamaha royal star. Brakes are not linked and im sure there is no air in the system. Rotors and pad s dont look contaminated.
I have ben told that a pot in the caliper may not be moving the full range, and that the rotors may be glazed from over heating.

 

[Rudy]

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Three things come to mind that could cause this...

1. Air in the line

2. Using non-sintered pads

3. Having a worn (non-flat) rotor contact surface.

Don't know squat about no Yammy Mammys.

 

[Anim8or Earl]

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Air in the line would probably make the lever/pedal feel soft. Sticking pistons could be the issue, they could be crudded up.

 

[CaptainMidnight85]

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If there is no air in the line, then I'd tend to go with contaminated pads. Rotors that are glazed would have a chrome-like surface, so that should be easy enough to tell. I'd surface the rotor(s) and replace the pads.

Could be weak fluid. Not that there is any real strength to it, but if there are semi-solids in there for some reason then the lever could go sponge-a-billy on 'ya.

Pads and fluid are cheap compared to tendonitus/carpul tunnelof the right forearm.

 

[DrAce51]

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Anim8or Earl wrote:

Air in the line would probably make the lever/pedal feel soft. Sticking pistons could be the issue, they could be crudded up.

what he said !

 

[Rudy]

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DrAce51 wrote:

Anim8or Earl wrote:

Air in the line would probably make the lever/pedal feel soft. Sticking pistons could be the issue, they could be crudded up.

what he said !

That could be but I have generally seen sticking pistons not release the pad more so than not activating the braking due to the strength of hydraulic pressure on and passive release.

 

[peterbilt]

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its not that old of a bike maybe go to a dealer in your area that deals in those bikes and see what the service dept says

i know using a lesser quality brake will cause issues, if there was air in the system you simply wouldnt have brakes,

maybe the master cylinder isnt putting out the right ammount of pressure maybe the fluid is just blowing past the bypass or seals its really hard to be accurate on a issue like this

i would higly reccomend to take it to a local shop or dealer that sells and works on those style bikes and have them take a look at it, worst case is you'll be out a few bucks for their time but its a small price to pay for peace of mind

 

[vtxcandyred]

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The experience I have had in the HARD braking area has been calipers not sliding. The ONLY way to be sure they are sliding equally is to disassemble and free up the slides.

 

[DrAce51]

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Rudy wrote:

DrAce51 wrote:

Anim8or Earl wrote:

Air in the line would probably make the lever/pedal feel soft. Sticking pistons could be the issue, they could be crudded up.

what he said !

That could be but I have generally seen sticking pistons not release the pad more so than not activating the braking due to the strength of hydraulic pressure on and passive release.

yes good point , also possible frozen brake pad slider pins , pads frozen in the caliper bracket , ( the two i mentioned would also cause a wheel to lock up ( not spin freely in some cases )

 

[ALEX BERECZKY]

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If the rotor are glazed, then you might be able to remedy that by using 220grit sandpaper to lightly sand both the rotor and the pads, so as to remove that glaze.

I do this every time I have the brakes apart, simply as a preventative measure.

 

[vtxcandyred]

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ALEX BERECZKY wrote:

If the rotor are glazed, then you might be able to remedy that by using 220grit sandpaper to lightly sand both the rotor and the pads, so as to remove that glaze.

I do this every time I have the brakes apart, simply as a preventative measure.

I tend to do this too but I use a coarse grit disc on my air die grinder. Its like a scotch brite pad. It will not take too much off.

 

[newday777]

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Your rubber lines are probably stretching when pressure is applied. If moisture has gotten in the system, bike sitting outside, unheated shed where high moisture in cold seasons happens as temps rise and fall of heat and cold will cause condensation in the hydrolic systems, the water and brake fluid cause an acid condition that deteriorates the inside of the lines, weakening them, and flex happens when you apply the brakes. This will happen to any brake/clutch fluid system when exposed to introduction of moisture and the brake fluid is not changed yearly.
The cure; put on stainless steel lines and new brake fluid yearly.

 

[vtxcandyred]

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newday777 wrote:

Your rubber lines are probably stretching when pressure is applied. If moisture has gotten in the system, bike sitting outside, unheated shed where high moisture in cold seasons happens as temps rise and fall of heat and cold will cause condensation in the hydrolic systems, the water and brake fluid cause an acid condition that deteriorates the inside of the lines, weakening them, and flex happens when you apply the brakes. This will happen to any brake/clutch fluid system when exposed to introduction of moisture and the brake fluid is not changed yearly.
The cure; put on stainless steel lines and new brake fluid yearly.

^^^^^^^^^^^^^^^^^^^^^^^^What he said TOO!!!!!!!!!^^^^^^^^^^

 

[Bufallowing]

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Two questions:

Did the Yammy started doing this when? After working on the brakes?

Did you have a shop do it, or did you work on it yourself?

Second: You said it was very hard to stop the bike. Is the lever spongy or solid? (Soft/spongy=air ; hard/solid=glaced pads&rotors, stuck pistons, etc.)

Bleed that front lever on every banjo bolt, starting with the one closest to the reservoir. You said the front and rear are not linked, if you have two rotors on the front, do the one with the shortest line first, then the other. You can leave the traditional purge on the caliper at last. That is a good way to make sure there is no air. I don't know what Yammaha recomends DOT4? (I don't play the piano) Make sure you are using what the manufacturer recommends.

Keep us posted.

 

[maxt]

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I had a similar problem years ago. I found my problem to be at the brake lever. It would bind when I pulled it in but release just fine when I let it out. I removed it cleaned and put a light lube where it was rubbing and at the pivot point. Worked fine after that.

Max T.

 

[DaveO430]

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I am in the sand the glazing from the rotors and pads or get new pads camp. Most of the other suggestions would cause either soft pedal/lever or dragging brakes.

 

[glhonda]

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Since it's a '96, is there a possibility the master cylinder has been replced with an aftermarket unit? If the bore is different from the original, you will lose the hydraulic advantage, giving a hard pull with less braking power.