Do you use the front brake much?

[Clint]

Yup. It's hydroscopic by design to maintain the fluid's integrity.

[Gixxerman]

Originally Posted by KD57

I seldom use the rear brake. Changed pads last nite on the Harley and the front was nearly gone, and the rear looked new. Since I just got back into street bikes a few years ago, I was wondering how that differed from off-road. I go thru front pads 5x more than rear pads on dirt bikes. I guess when I get on the street using the front just carries over from dirt. I do use both on a panic stop, street or dirt.

If you seldom use the rear brake I would suggest not to combine them in an emergency. When panic strikes, you most likely will lock up that rear tire.

[Uncle B]

Yes I use the front brake and the rear.

[omegajim]

So do I need to create a new thread about how often people change their brake fluid?

[Gixxerman]

I change it every year, even though I don't have to... So do I make it to the finals

[GSX1100FL]

I use both front & rear.

[inspiron]

I don't have enough confidence in my own skills to mess with the brakes. I'll leave that up to the professionals until I get some training how to correctly work on the bike.

[Rickster]

Changing brake fluid is time consuming, and sometimes messy, but not difficult at all.

[CaptCrashIdaho]

Two words: Vacuum Pump.

[omegajim]

In Inspiron's case, he's in Switzerland, so who knows what you all have to do with the old brake fluid.

Probably more trouble than it's worth in the EU.

[Uncle Bob]

Originally Posted by CaptCrashIdaho

Two words: Vacuum Pump.

Please keep in clean, this is a family site.

[CaptCrashIdaho]

Originally Posted by Uncle Bob

Please keep in clean, this is a family site.

HEY! I didn't use the Austin Powers voice! Jeepers....

[omegajim]

HEY! I didn't use the Austin Powers voice! Jeepers...

You know, there had to be a reason I never used the word "vacuum" here, and I think we all found out why.

[KD57]

Originally Posted by Gixxerman

If you seldom use the rear brake I would suggest not to combine them in an emergency. When panic strikes, you most likely will lock up that rear tire.

Nope, I have a pretty good feel for the rear too, just don't use it much. I've had to make several panic stops, w/ incident. Twice I had a passenger on the bike. Back on the topic of changing fluid, I change it every year.

[Rickster]

I thought the topic was "do you use the front brake much".

[KD57]

It is, but I was referring to the second, third?? hi-jack topic.

[MikeHump]

Isn't approximately 75% of braking on the front wheel anyways? (assuming both front and rear are applied evenly) Also, on some new bikes don't they link the front and rear, so that when one is applied, some (not much) hydraulic pressure is applied to the other?

When it comes to changing brake fluid, if bikes use the same brake fluid as cars, it should be changed any time the system is opened. Also, when replacing pads/rotors, when compressing the caliper piston you should open the bleeder screw so that the brake fluid at the caliper is bled out. Otherwise, the dirt from around the piston will be pushed back into the brake line and dirt = corrosion. Also, sometimes metallic flakes build up due to corrosion (if too much water/dirt does get in) and brake fluid actually starts conducting electricity. A maximum of 0.3 volts (if you happen to have a voltmeter handy) should be allowed in brake fluid before too much damage starts occurring.

[Rickster]

Originally Posted by MikeHump

Isn't approximately 75% of braking on the front wheel anyways? (assuming both front and rear are applied evenly) Also, on some new bikes don't they link the front and rear, so that when one is applied, some (not much) hydraulic pressure is applied to the other?

When it comes to changing brake fluid, if bikes use the same brake fluid as cars, it should be changed any time the system is opened. Also, when replacing pads/rotors, when compressing the caliper piston you should open the bleeder screw so that the brake fluid at the caliper is bled out. Otherwise, the dirt from around the piston will be pushed back into the brake line and dirt = corrosion. Also, sometimes metallic flakes build up due to corrosion (if too much water/dirt does get in) and brake fluid actually starts conducting electricity. A maximum of 0.3 volts (if you happen to have a voltmeter handy) should be allowed in brake fluid before too much damage starts occurring.

It's always interesting to hear all the different theories people have picked up from there experiences.

I'm not saying it's not true, but I have never heard anyone talk about there possibly being a Voltage charge in your brake fluid. I guess if you had some sort of chemical reaction between the fluid, and the metal particles it would be possible, but that would mean that either the fluid, or the particles would have to be acidic. Also, it seems to me that you would have to drain the fluid in order to test it, and if that's the case, I sure wouldn't be putting the old fluid back in, even if it tested OK. Guess I need to do some research.

Seems to me that if you were to get dirt around the piston and into the brake lines, the seals would already be so bad that you would be forcing brake fluid out (leaking) every time you applied the brakes, and a rebuild was already in order.

Personally, I never open my bleeders unless I have pressure on the system, IE. brakes applied, than I close the bleeder again before I release pressure on the brakes. I've always been told that if you open the bleeder without pressure on the system, you run the risk of getting air in the system, and causing the brakes to feel spongy and need pumping up every time you apply them.

As to the fluid, it will say on the master cylinder cover what type to use, in some cases it is the same as cars. The most common one I've seen is DOT-4.

[themeatmanlandry]

Originally Posted by MikeHump

Also, when replacing pads/rotors, when compressing the caliper piston you should open the bleeder screw so that the brake fluid at the caliper is bled out.

That makes a lot of sense. I can't believe I've never heard that before.

To answer Rick's question, I have a cheapo brake bleeder bottle that basically amounts to tube submerged in brake fluid such that anything drawn back into the system will be brake fluid.

[MikeHump]

Originally Posted by Rickster

It's always interesting to hear all the different theories people have picked up from there experiences.

I'm not saying it's not true, but I have never heard anyone talk about there possibly being a Voltage charge in your brake fluid. I guess if you had some sort of chemical reaction between the fluid, and the metal particles it would be possible, but that would mean that either the fluid, or the particles would have to be acidic. Also, it seems to me that you would have to drain the fluid in order to test it, and if that's the case, I sure wouldn't be putting the old fluid back in, even if it tested OK. Guess I need to do some research.

Seems to me that if you were to get dirt around the piston and into the brake lines, the seals would already be so bad that you would be forcing brake fluid out (leaking) every time you applied the brakes, and a rebuild was already in order.

Personally, I never open my bleeders unless I have pressure on the system, IE. brakes applied, than I close the bleeder again before I release pressure on the brakes. I've always been told that if you open the bleeder without pressure on the system, you run the risk of getting air in the system, and causing the brakes to feel spongy and need pumping up every time you apply them.

As to the fluid, it will say on the master cylinder cover what type to use, in some cases it is the same as cars. The most common one I've seen is DOT-4.

Well, as far as the metallic flakes in the brake line, it takes A LOT of corrosion and abuse for that to happen, but it is possible. This is also assuming that bikes have metal brake lines similar to cars. I'm not sure if they do, because of how much smaller bikes are. Any type of moving fluid with any kind of metal in it will produce a small amount of voltage. All you have to do to test it is take a voltmeter and open up the resevour (spelling?) and put the tip of the voltmeter into the fluid and it will give you the reading. The maximum allowable voltage is 0.3 volts, according to state regulations.

When it comes to bleeding, when you compress the piston back into the caliper, you are putting pressure on the system, and the dirty fluid at the end near the caliper should be bled, and then the resevour should be topped off. I've actually done this, and it makes sense. You are correct about opening the bleeder and getting air in the system though, but most brakes are low-drag brakes, and they are always slightly applied. To test that theory, just open a bleeder screw when your bike/car is just sitting there, and watch a little bit of fluid drip out, due to a little bit of pressure.

These are just the things that the industry professionals have been teaching me. However, all of this knowledge is textbook knowledge and stories of actual events from instructors, and this varies a lot from actual shop experience, which I lack. I'm not sure how often the metallic flakes in the fluid occur, or how damaging it is to the brakes if you don't bleed off the dirty fluid near the caliper when compressing the piston, because I've not seen it firsthand.