Why You NEED TO REPLACE Original brake lines w/pics

How many times have we heard this:

"why do I need to replace my brake lines, they look fine?"

Why indeed.

FIRST REASON: YAMAHA said they were only supposed to last FOUR YEARS. Four. Not thirty.

Check your date codes.

Sometimes they're easy to see:




Sometimes you really have to look (this one says 5/82)




EVEN MORE IMPORTANT REASON:

I "sectioned" a couple of old lines (12/80 and 5/82) to see exactly what we're dealing with.

There is an outer rubber sheath, then a layer of metallic-appearing (but it's NOT) woven cloth (nylon?) then the red rubber outer-inner hose, with a woven layer fused between it and the black inner liner. That part won't peel apart, it's bonded/molded together.




NOW LET'S EXAMINE THEM MORE CLOSELY. See pic below.

Note that in the hose on the left, you can see the inner black hose cracking and crumbling away. It's even more frightening under a magnifying glass, I think the Canon got a good look though.

Note that in the hose on the right, there is a readily visible SPLIT in the inner hose.

CRACKING, CRUMBLING AND SPLITTING OF THE INNER HOSE:




DOES ANYBODY NEED ANY MORE CONVINCING? I got more old brake hoses I can cut up...

Besides, stainless lines are sexy...



C'mon, people. Just because you can't readily SEE the problem, it's there.

Replace your hoses. You can get original-type hoses if you don't want to upgrade to stainless; but replace your old hoses. With NEW ones.

 

Fitz, another phenomenal write up. Good job getting the cracks on the inside on film. Can tell that is not the easiest thing to do.

That first inner layer looks to be nylon braid. Looks just like marine dock line. Which if exposed to moisture can break down as well. So any cracks on the outside could potentially break that down as well.

Really glad someone finally did this. I was thinking of doing it to mine once I got them off the bike to just see. Did you by chance split one down lengthwise to see the whole of the damage? that would be interesting I think, although possibly hard to do with all the layers in there.

Great write up Fitz!

 

Great job Fitz !! I've been looking for a brake thread to add to my "New Here" warnings - now just add some nasty caliper shots !

 

Thanks! I'll try splitting one (or at least a section of one) lengthwise. The cracking and crumbling for sure goes on up inside the hose as far as a flashlight can see; but the camera just refused to cooperate on focusing into a "black hole."

It took me about 3 dozen shots to get one good one; the faded date code was nearly as difficult.

The fact of the matter is, even though they look "fine" on the outside, bad things have happened on the inside.

I don't think Yamaha intended a 26-year "built-in margin" of safety. Ten years instead of 4, maybe; but not 30.

 

Time, I have some pictures that I took of the Caliper and the MC as I took them apart this winter. If you want I can post them up. Don't want to hijack Fitz's Thread here thou.

 

Start a new one here in "FAQ Suggestions" and call it "why you need to rebuild your caliper and M/C w/pics."

Let's keep this one about brake lines; but I welcome anybody else that has deteriorated brake line pics to add those here.

 

Thanks Fitz
I replaced the lines of my '77 XS650 a few years ago with braided SS lines, I wonder if I kept the original ones on a shelf...if so I will split a few sections, will take pictures and will post them here for sure.

I hope my camera will not challenge me too much!

Edit: no luck, I probably throw them in the garbage can! But I will split the ones off of my Seca 900 when I replace them.

 

Switching to new brake lines is likely to be the biggest improvement in handling you will ever experience on your XJ, esp. if you put in Stainless Braided ones.

You can rejet, tune, get grippy tires, even replace shocks....but a good stop is something you notice!

 

Is there a time when even stainless brake lines need to replaced?

 

They're Teflon wrapped in Stainless Steel covered in PVC.

I'd give them 10 years, then take them somewhere and have them hydrotested. If they're good, another 10 years.

None of those 3 things are subject to much deterioration. Of course you should inspect them regularly.

 

There are different styles of braided lines.

The better ones are as day7a1 says, Teflon wrapped in Stainless Steel covered in PVC. Those should last close to forever.

The other ones are the ones that have the steel braiding, but not the PVC jacket. Those I would pay closer attention to, since the braiding can retain liquid. There is no telling what might get in there and how it might affect the hose inside, so I'd check those periodically for soft spots.

 

OMG ... bigfitz ... I just checked my hoses ... 6/83 ... I'm grounding myself!
Help ... LEN!!

 

Not that I want to minimize the consequences of cracked brake lines on performance and rider's safety, but it came to my mind that I've seen number of times badly cracked intake boots that were not leaking at all.

I know that there is no fluid pression in intake boots, so it is hard to compare, but brake lines are multi-layered exactly to make them stronger, so I tend to think that as long as the outer rubber shell is good, it would prevent the inner rubber layer to blow out.

I may be wrong, it happens all the time...

 

The lines I cut open are crumbling badly enough that they could introduce little "crumbs" of rubber into the system.

Yamaha said they were supposed to last FOUR YEARS. Apparently they knew they wouldn't last oh, say... 30 years?

 

I clearly understand that.

I have to ask: were these lines off of a running bike or have they been drying on a shelf for years before you decide to cut them in pieces? SOme carbs parts can shrink badly when not in use, couldn't it be the same for brake lines?

 

I ran into a problem with my XS where the rubber crumbs plugged the little hole in the master cylinder, which caused my brake to not release sometimes. This required a complete rebuild of everything to clean the crud out.

Floaters in your hydraulics are not a good thing.

 

I took my brake lines off of a running bike that had seen daily use. There were tiny bits of what I assume to be the inner hose that came out when I removed the lines. I have personally experienced the consequences of hydraulic hoses failing due to age (thankfully it as on a piece of stationary machinery). It's very difficult to tell that the hose is old unless you look at the build date. It's true that rubber that has sat out in the weather will show cracking over time, but that happens long after the interior of the lines have began to degrade.

 

I'll definitely cut the hoses, and "expose" the results .. The brake hose thing also happened on my MG .. I was driving it, made one brake application and the brakes locked ... particles from old lines clogged the return path of the fluid, heated, expanded ... well you get the picture.

 

The way I see it, particles or tiny bits of inner hose are more to worry about then the hose itself to blow out. When they make your brakes lock up, that aint funny.

 

Both came off "running" (but not that I'D RIDE) bikes. Max time on shelf: 3 years for one set, four for the other. Does it make a difference if they sat empty on the bike or empty on the shelf for a couple more years? Shall I go cut up the lines off my 650, which is still together? They're probably worse.

Why is it so hard to believe that 30 year old brake lines just might not be viable any more? Did Yamaha miss something?

Brake shoes delaminate. I'm 3-for-3 on my XJs with that one. Shall we debate that too?

THIRTY YEAR OLD BRAKES ARE DANGEROUS.

Period. Not a point of argument, a fact.

I simply posted some proof for those who don't believe in using NEW, "store-bought" parts for certain things. Some things can't be short cut.

 

I'm not arguing, I'm just asking questions. Thank you for frankly answering about the hoses you used for your test.

This said, I do think that your test is valid and your point of view is right.

I also tend to think that some of these old brake lines are still good, because all these bikes haven't been ridden and/or serviced and/or stored all the same way.

The problem is that nobody can't tell just by looking at them. Better change them, for sure.

 

Wait... I cant just rinse these out with some water and throw em back on???



kidding - but for real, a friend of mine has a suuuuuuuuper nice camera, i'll cut mine open and see what kinda pictures i can snag with her macro lens

 

Please do! I really want to see how bad are yours. Actually, everyone who will replace his old lines in the following weeks should cut them, picture them and post them here.

Please do it, whatever their actual condition.

 

but you can reuse those copper washers.work hardening is what happened to them the first time they were used, makes them too hard to flatten out and seal right again.
heat them red hot 2 or 3 times, let them cool slowly and sand flat with fine wet/dry paper and they'll be good to go.
not saying you shouldn't buy new ones but if you forgot or something, don't let it stop progress

 

So here is round two of looking down the rabbit hole. These lines literally JUST came off the bike. Just mounted the SS lines and walked inside to tear into these babies. One was DOT 10/80 and the other DOT 9/80.

The inner liner on these unlike the ones that we saw from fitz are not too bad. Actually in surprisingly good shape.



So I decided to start cutting them lengthwise. This one you can see a little bit of cracking in the very center of the cut area. Again not bad.



Now here is the real shocker to me. I looked down the outsides for signs of area's where there may be problems and found some cracking in the outer layer around the area where the line is held to the fender. I cut that area open and found this.



That is a straight line cut. I double checked. The middle layer has swollen there and is creating a choke point. I'm assuming that under pressure this could be dealt with, but it looks like the beginnings of a heart attack if you ask me. Or a ticking time bomb, not sure which.

Anyway, I have some pretty SS lines to go bleed life into.

 

Very interesting! It seems like the hose has worn a lot more at the stress of (friction) point. Is the inner line just swollen or also cracked at that point? I can't see very clearly even if your pictures are quite good.

 

There is some minor cracking along the whole area that I cut open in that picture. Nothing deep though. Just the surface is cracking, probably from the swelling pushing the liner the opposite direction to which it was designed.

 

Is there any crack that seems like it could go all the way through the inner layer soon?

 

I just spread it as wide as I could and at the top where you see the beveled cut one of the cracks goes all the way through to the mesh middle layer.

 

Do you feel it could have been possible for you, under close inspection, to notice these damages to the outer layer (cracked, swollen area) before you started pulling it off of the bike? Or was that section covered with a rubber protective sheet like the ones we can see mntbikecrazy55 brake hoses picture?

 

Those protective spots on the 650 maxim are on the master cylinder to joint line where it contacts a positioning ring behind the headlight bucket. Where this piece was located was behind the rubber boot that contacts the hook on the fender that guides the line. See Fitz's picture of his SS lines and you will see the rubber boot I am speaking of.

 

That's OK now, I know what you mean. It also answers my question: basically, it was impossible to notice these damages before pulling the hose off of the bike.

 

The problem is that you don't necessarily see things that are wrong. That's why engineers do non-destructive testing. You can't rely on your bare naked eyes.
The rubber in brake lines simply breaks down. It oxidizes, corrodes in a process similar to rusting, except you can't see it.
Sure, you can take your brake lines off after 30 years and maybe they look like crap. But if you take them off a year or two after their expiration date, then they will most likely LOOK fine. They are not fine. Their properties are out of spec, but you don't have a way to measure them.

Honestly, you're better off saving money by sending your engine oil to the lab instead of replacing it every 2500 miles. It's probably fine anyway (oil has come a long way in 30 years), but it's testable, so you'll know if it isn't. You can't test the brake line, you just have to replace it.

There's no point in showing pics, or even looking at them. Look at the date, that's IT!

 

Another valuable PSA from BigFitz. Of all the things I have done to my Seca the SS lines were absolutely the most amazing. I just picked up an 04 Concours and I have to say that my the front brakes on my Seca are every bit as good if not better. The Kaw will get SS lines eventually

 

this is just another reason I am super glad I found this forum! thanks to fitz for this thread and many others. I just checked my new to me 83 maxim. the date on the lines appears to be 1983! yes, possibly original equipment! does anyone have a good suggestion for what ss brake lines are the best bang for the buck?

CN

 

I'm pleased my pup chewed my original lines, just gotta do the anti dive and rear lines now. Was really P'd off at first cause they looked fine on the outside. $75.00 NZ per side custom made so probably another $150.00 will sort the anti dive and the rear. peace of mind for very little.

 

Finally took the old lines off last night as I went to test-fit some new SS lines from Chacal. I'll cut them up tonight and get the pictures on here soon.

You know when you go to change a lightbulb on a ceiling light, and there's a bunch of old dead bugs collected in cover? I can definitely report so far that the MC reservoir looked like someone had emptied said bugs into it. I'm guessing that's bits of deteriorated rubber from the inside of the tubes.

 

That's exactly what it is.

 

Ok, so here's the results.

First, let me say that I understand now why not too many of you have cut them open for pictures. That was really difficult! I had my hands covered in brake fluid and I was handling razor blades and pulling hard on the lines and doing my best to keep a straight line without snapping a blade or losing a finger (or an eye!).

Second, big disclaimer: Fitz, don't get me wrong - I'm glad I'm getting new lines. I don't think anyone should have rubber hoses this old. Everyone go get new lines regardless of the material.

Now that the disclaimer is out of the way, I'm honestly a little disappointed. My lines look fine on the inside. I was hoping to see ruptures all over the place, but they look smooth. Maybe in one or two spots there's a little brown buildup, but not bad for 33 years old. The few times that it looks like there may be swelling, there's not. That's just where my utility knife went astray.







And just to show you, that looks like "DOT Somethingsomething 11/81" to me. As in November of 1981. I was 7 months old when that thing was last inspected.


Now, here's where it truly gets scary. I opened up the master cylinder, and this is what I found. Looks like bug mash, doesn't it?


And this is the brown sludge that came out of the MC when I squeezed the brake lever.


So there you go.

Now what I wonder is whats going on in the brake caliper. Is that were the bug mash came from, cause I'm having a hard time believing that's years of built up rubber liner residue. Fitz, I'm looking to you.

 

YUCK.

The "bug mash" is dried brake fluid and bits of the various seals as well as remnants of the insides of the hoses. Primarily just dried-up brake fluid.

In the third pic down, I see what appears to be a lengthwise split in the inner line a few CM long. The date (11/81) is when the hose was made, not just inspected.

The apparent rust is a concern; there are very few ferrous parts in the system. Be sure you completely disassemble the M/C and carefully inspect the bore when you rebuild it.

I wonder what the caliper looks like?

 

Wouldn't be surprised if the caliper looks something like this:

 

Great. Can't wait.

Where's the caliper-rebuild thread, again?


Also, don't worry about my master cylinder. I have flat handlebars now, and Len hooked me up with a new master cylinder that will sit a little more level.

 

BaldWonder

I'm not suprised with what you found, the stuff I had in my calipers looked even worse than yours. It felt like "caramel" or heavy brown grease if you prefer.

Do you know the last time brake fluid was changed?

 

I've owned the bike for three or four years now and have never touched the brakes until now. I imagine the same goes for all of the other previous owners. I know there have been at least three previous owners, but I have the impression there have been many more.

Good thing I know better now, eh?

 

Yeah scary to think you've been riding around with the brake system in that condition. I rode a whole season before rebuilding my brakes and I gotta say it really freaked me out when I pulled the piston from the caliper and saw what you see in the pic above.
Cleaned and honed:


Here's a link from Chacal's information overload thread on rebuilding:
http://www.xjbikes.com/Forums/viewtopic/t=12529.html
Be sure to get all the crud from the groove that the seal sits in or the piston will bind. I used a dental pick to scrape it out and a wire wheel in a dremel.

 

***TIP***

"Kiss" the baked-in crud with the flame from a propane torch; don't get the metal even hot. Just scorch the crud.

The crud will then crumble and you can easily dig it out with ***TIP #2*** a sharpened kitchen bamboo (shish-kebob) skewer.

The small brass wire brush in the Dremel is a wonderful thing as well.

The seal channels need to be dentally clean.

 

Perfect, thanks! And it just so happens I do have a dental pick and a Dremel. And an excuse to play with fire.

 

Hey Guys,

Looking to replace the brake lines as indicated here. Yet another great piece of advice! One question: Why are there 2 brake lines with a joint instead of a single brake line the whole way down?

 

I forget where I saw it (may have been earlier in this thread, actually) but someone else had asked that question. The answer seemed to be that this was a manufacturing tactic, since some of the other models have dual disc brakes and required three lines and a joint. The single disc models get to use the same parts minus one. Hurray for mass production.

I believe Len has a single line replacement available. I opted to keep the joint as I think I may upgrade to dual disc in the future.

 

Actually, we do not have a single-line replacement available. And, you actually want to keep that elbow or joint as part of the system; it is hard steel and doesn't "give" at all (even the braided lines have some give to them). Think of it this way: the ideal brake system would be nothing but hard steel all the way from the master cylinder to the calipers......that way, there would be no expansion, at all. Flexible lines have to be used in the real world, though. You want to minimize the use of them, though, so keep any hard steel sections (the elbow).

As an aside, the pre-production mock-ups of the 750 Seca models actually show a brake line system which is almost entirely hard steel lines, with just a short piece of rubber hose at the calipers. XJ750 Seca and 900 models actually use a lot more hard steel lines than other models (to "link" the m/c to the distro joint(s), and just like automobiles, the XJ1100 models use a hard steel line from the front to the rear (the XJ1100 models has "linked" front and rear brakes).