2006 ST1300 ABS 46k odo Rear Brake locks up

[Kevcules]

On a slightly different, but related, note.......why is it that bike brake systems need to be flushed and fluid changed so often, as compared to cars? Admittedly, my cages have not had the brake fluid changed out in all the time that I have owned them and the brakes function just fine. A friend has a hydrometer for measuring moisture in brake fluid. I think I am going to borrow it and test the fluid in my cages. May be interesting.

I still wonder the same thing as I flush the brush the brake fluid yearly and not have to do that to any other machine that I've owned.

I actually just bought a digital brake fluid tester after discussing the subject with locals and online forums like this one.

I didn't get a reading on the ST fluid yet, but I will when I flush it again for the 7th time in 7 years in the spring.

I did test and replace the brake fluid in two of my vehicles recently. I tested 7yr old fluid in my car at 1.8% . I then tested the new fluid in a sealed container at 1.5%. The gauge gives a warning at over 2% and says to change it at over 3%. I was all set to do the job so I did it, but the tester says that I didn't need to.

 

[Kevcules]

How do I manipulate the smc while turning the back tire

Just push up on it while laying beside the bike on the left side. (the direction the caliper would move if the front brakes were activated while the wheel was turning forward)
It should move up a little bit and stop the rear wheel right away.

 

[jfheath]

..... and then release the rear wheel immediately on letting go.

Regarding brake fluid - I don't think cars use DOT4, do they ?

 

[Kevcules]

..... and then release the rear wheel immediately on letting go.

Regarding brake fluid - I don't think cars use DOT4, do they ?

Yes.

 

[Andrew Shadow]

On a slightly different, but related, note.......why is it that bike brake systems need to be flushed and fluid changed so often, as compared to cars?

I have no idea what the recommended schedule is on new cars, but years ago the same two-year interval was the recommendation for cars as well. Nobody ever did it.

I suspect that the biggest difference between cars and motorcycles is exposure, mostly to heat and specifically heat cycles. Motorcycles have the brake lines running very close to very high heat sources as a matter of necessity due to lack of space. This causes much more exposure to heat/cold cycles than are experienced with cars where the all of the brake lines are far away from direct heat sources for the most part.

 

[Al st1100]

I have no idea what the recommended schedule is on new cars, but years ago the same two-year interval was the recommendation for cars as well. Nobody ever did it.

I suspect that the biggest difference between cars and motorcycles is exposure, mostly to heat and specifically heat cycles. Motorcycles have the brake lines running very close to very high heat sources as a matter of necessity due to lack of space. This causes much more exposure to heat/cold cycles than are experienced with cars where the all of the brake lines are far away from direct heat sources for the most part.

the maintenance schedule for the 2012 Nissan Leaf recommends replacing the brake fluid every year or 15,000 miles under “Severe Service,” and every two years or 30,000 miles
BMW CARS Every 30,000 miles, or every three years
there has been synthetic dot 3 for a while now some manufactures say 3 yrs some say 100k. I think the longer intervals use synthetic which is more resistant to moisture. The way some people drive aroud here the Car fluids are exposed to more heat.

 

[ksalam]

Symptoms are of a stuck SMC. You can test it as follows: bike on center stand in neutral engine off, while manually rotating rear wheel, rotate SMC [left front disc brake] forward and see that the rear wheel stops. Let go of the SMC and see that you can again freely rotate rear wheel.

I have an 03 my back wheel frozed I bleed brake by watching a video but it's still not giving 2nd or 3rd

 

[Sadlsor]

I have an 03 my back wheel frozed I bleed brake by watching a video but it's still not giving 2nd or 3rd

But did you test the Secondary Master Cylinder as described above?
Bleeding the brakes improperly does very little good, certainly not as pertains to the SMC. It's an easy process, but very detailed and quite specific.
"Good enough" is not really good enough in this case. Do it correctly, or drive yourself crazy, and wreck bike parts at the same time.
And what do you mean by "giving second or third"?

 

[ksalam]

But did you test the Secondary Master Cylinder as described above?
Bleeding the brakes improperly does very little good, certainly not as pertains to the SMC. It's an easy process, but very detailed and quite specific.
"Good enough" is not really good enough in this case. Do it correctly, or drive yourself crazy, and wreck bike parts at the same time.
And what do you mean by "giving second or third"?

So after my back break froze I took pad out not realizing the abs won't let me ride with just front breaks . When I went to ride and only would ride In first gear I can tell it's going into the other gears but there is no pressure pushing the bike so its like I'm In neutral

So after my back break froze I took pad out not realizing the abs won't let me ride with just front breaks . When I went to ride and only would ride In first gear I can tell it's going into the other gears but there is no pressure pushing the bike so its like I'm In neutral

I would appreciate any help

 

[Sadlsor]

Start by reinstalling the rear brake pads correctly, and NEXT perform SMC test as above.
Using magnifying glass icon in the blue bar, Search for SMC... much discussion to be read, in the Articles section.
Then we'll tackle the "no pressure pushing the bike."
Sort the brakes first.

 

[TerryS]

You are a much braver man than me! That bike sounds like it has multiple problems.
1. Locked back brakes are a symptom of a seized or blocked secondary master cylinder; bleeding at the caliper won't fix that unless the only fault is a seized caliper piston
2. The ABS does not know whether the pads are there or not; it checks wheel speed rotation only, Certainly doesn't stop the bike running in the upper gears
3. No drive in upper gears? Most likely a clutch failure, either at the master or the slave. Nothing to do with the brakes (unless the back brake is so seized the engine can't turn the wheel!)

Hope you are good at rebuilding hydraulic systems.

 

[ksalam]

Start by reinstalling the rear brake pads correctly, and NEXT perform SMC test as above.
Using magnifying glass icon in the blue bar, Search for SMC... much discussion to be read, in the Articles section.
Then we'll tackle the "no pressure pushing the bike."
Sort the brakes first.

So the brakes are great now everything let go the wheel is turning and I had someone press on break it stopped and I was a able to spin it

So the brakes are great now everything let go the wheel is turning and I had someone press on break it stopped and I was a able to spin it

I bleed them remove all old brakes fluid per the YouTube video at first I was not getting anything out of one of the bleeding plugs in rear but now it flows clean

You are a much braver man than me! That bike sounds like it has multiple problems.
1. Locked back brakes are a symptom of a seized or blocked secondary master cylinder; bleeding at the caliper won't fix that unless the only fault is a seized caliper piston
2. The ABS does not know whether the pads are there or not; it checks wheel speed rotation only, Certainly doesn't stop the bike running in the upper gears
3. No drive in upper gears? Most likely a clutch failure, either at the master or the slave. Nothing to do with the brakes (unless the back brake is so seized the engine can't turn the wheel!)

Hope you are good at rebuilding hydraulic systems.

So at first that's what happened it was frozen had to remove break line and pad to free up backfire