replacing brake and clutch hoses

[upjeeper]

i saw somewhere the recommended interval for clutch and brake hose replacement is 3 years. i suspect that BS to get people to buy more parts. I would guess (no way to know) that the hoses on my Valkyrie are the ones that were on there the day it rolled off the line.

Opinions or advice please?
thanks!

[Ricky-D]

Si,  the hoses are forever items.

Only if they are degraded to the point of leaking would they need replacing.

***

[Disco]

I call BS on the 3 year interval.

Only if they are degraded to the point of leaking would they need replacing.

Or, if you want to be sure your old lines are not swelling under pressure and not transmitting all the force to the calipers.  Mine were 11 years old and I want all the brake I can muster.

[Valkpilot]

i saw somewhere the recommended interval for clutch and brake hose replacement is 3 years. i suspect that BS to get people to buy more parts. I would guess (no way to know) that the hoses on my Valkyrie are the ones that were on there the day it rolled off the line.

Opinions or advice please?
thanks!

I replaced my brake and clutch lines at 50,000 miles.  The bike is 12 years old.  The rear line was so swollen internally that I could hardly push fluid through after disconnecting the caliper.

They last a long time, but they aren't 'forever' items.

By the way, braided stainless steel lines provide a noticible upgrade in brake feel and response.

[Ricky-D]

I can't understand the difference between steel braided encased brake lines and stainless steel braided encased lines!

I know stainless braided encased hydraulic lines are prettier but that is where the difference ends.

Honda steel braided encased lines are covered with a rubber that is much more weather resistant and will outlast any aftermarket brake lines by a factor larger than two. Probably more like a factor of four!

[Wildman]

Braided stainless brake lines are a huge improvement for people that do hard braking.
Do you lock your front wheel under controled conditons, to practice going to the edge of lock up, and then releasing the brake immedeately to recover. It's the only way to know where the edge is.
The edge of the traction limit.
If you can't do this you are not braking to the ability of the bike.
If you bractice this and lock them in the rain, or what ever, the brake release responce is built in.
You more likely, not, to go down.
Stainless braided lines are a must for this type of performance riding.

 

[GJS]

Honda steel braided encased lines are covered with a rubber that is much more weather resistant and will outlast any aftermarket brake lines by a factor larger than two.

+1

I replaced my stock 99IS lines with Stainless Steel Braided lines 3 years ago. I could not feel the difference after the upgrade.

Years ago I upgraded a bike I was riding and was amazed at the improvement, then. I was looking for it this time, but have to say, it feels the same to me.  Having said that I don't do any stunt or EXTREME riding moves.

If Honda does in fact use rubber coated braid, that would explain my experiance.

Cheers,

Glenn

[Ricky-D]

Just as an added note:

All flexible brake lines made for on the road use are under federal regulation and cannot be tagged for on the road use unless the meet federal standards.

There are no flexible brakes lines made that are not braided encased and meet the federal standard.

That means all the brake lines you can purchase for your Valkyrie are braided encased. Period!

So as far as personal observations regarding performance and differences. Well, sorry to say but it is all illusionary.

On my custom v-twin I run the small 3/16" OD nylon lines that are not encased with anything. These lines are not approved for on the road use and a disclaimer comes with the line as to that point! The nylon line is rated at 5k psi so for me, that is safe enough! On the v-twin, that is!

I mainly wanted to add this post to refute the idea that these Honda brake lines, or for that matter any brake line that is DOT compliant expands. That's bunk. It may stiffen with pressure applied but expand? No, I don't think so. It would never pass the standards.

***

[Valkpilot]

Just as an added note:

All flexible brake lines made for on the road use are under federal regulation and cannot be tagged for on the road use unless the meet federal standards.

There are no flexible brakes lines made that are not braided encased and meet the federal standard.

That means all the brake lines you can purchase for your Valkyrie are braided encased. Period!

So as far as personal observations regarding performance and differences. Well, sorry to say but it is all illusionary.

On my custom v-twin I run the small 3/16" OD nylon lines that are not encased with anything. These lines are not approved for on the road use and a disclaimer comes with the line as to that point! The nylon line is rated at 5k psi so for me, that is safe enough! On the v-twin, that is!

I mainly wanted to add this post to refute the idea that these Honda brake lines, or for that matter any brake line that is DOT compliant expands. That's bunk. It may stiffen with pressure applied but expand? No, I don't think so. It would never pass the standards.

***

It is possible to be DOT compliant and not be the best solution for the application.  Our OEM brake lines are constructed as they are due to a compromise of cost and performance.  All manufacturers must deal with such compromises in their designs.  While compliant with necessary standards, the flexible line design does not preclude hydraulic power loss at the caliper due to expansion. 

Your statements above do not take three critical elements into account:

• Braid material and coverage
• Core tube material
• Material changes with age

Here's a cross section of an OEM brake line.  It consists of a core tube that carries the brake (hydraulic) fluid, a serving of braid, a thin flexible covering, another serving of braid, and an outer flexible covering which is the encasement to which you refer.



Note in the picture below, that the braid servings are not metallic.  They are a textile material of some sort and it is not aramid fiber (Kevlar) or I couldn't have cut them without special tools.  (In addition, aramid fibers are prohibitively expensive for such an application.)



It's hard to see in the picture above, but the braid coverage of each layer does not cover 100% of the layer below.  Stainless steel braid encased cables are covered 100% by the serving of braid, limiting expansion not only through the strength and tensile rigidity of the stainless steel wires but through application of resistive compression on the entire surface of the core.  I suspect that the double serving of braid in separate layers is an attempt to compensate while still saving on materials.

The core tube material of the OEM line is a flexible, rubber-like material as illustrated in the picture below.  By contrast, the core tube of stainless steel lines made by Barnett, Goodridge, and Galfer are all of PTFE (trade name DuPont Teflon.)  PTFE and its close cousin FEP (also marketed by DuPont as Teflon for some applications) are near-miracle plastic  materials.  They are strong, relatively rigid, withstand high temperatures, and are pretty much impervious to chemicals such as brake fluid.



With age and continuous contact with brake fluid, the flexible rubber-like material in OEM brake lines begins to break down, resulting in reduced wall rigidity, which in turn leads to greater expansion under hydraulic pressure.  In addition, the material begins to absorb the brake fluid and swells, narrowing the passage in the core tube.  The combination greatly reduces hydraulic pressure transmitted to the caliper, reducing braking performance.

These considerations are important before declaring OEM brake lines "forever" components, flexible brake line expansion "bunk", and performance increases with stainless braid lines "illusory".

Every manufacturer of brake lines refers to expansion or swelling of flexible brake lines, as does every automotive site I looked at.  Either you are right and all of them are wrong, or all of them are right.  Assuming that all those sources are not victims of mass hypnosis, which of the two choices is most plausible?

[GJS]

  WoW!

Thanks for the great pictures and investigation ValkPilot!

As I mentioned, I have felt the difference once, but not when I did the Valk.
I think the Valk cables I replaced were probably still in good condition.

Best regards,

Glenn

[John U.]

Many thanks for shedding some actual light on the subject. 

[Ricky-D]

Thanks for the pictures you have posted and I admit that I was incorrect about the Honda lines being steel braided lines. I guess what I object to most is all the hype about replacement lines being such a superior product to the Honda Oem and reports by riders regarding their amazing discovery when having replaced their Oem lines with something else.

I mean to say that if you replace your lines with stainless braided lines because they add to the look you want for the bike, then say so! There's nothing wrong with that. But to declare a huge safety boost that you can feel is such bull and only is concocted to boost an ego and encourage envy and worst of all, sway the novice riders that they are riding second class equipment and push them to make the same type changes unnecessarily.

Further, I reject some of your statements couched in absolute terms. I want you to know however I'm not trying to start an argument with you.

""With age and continuous contact with brake fluid, the flexible rubber-like material in OEM brake lines begins to break down, resulting in reduced wall rigidity, which in turn leads to greater expansion under hydraulic pressure.  In addition, the material begins to absorb the brake fluid and swells, narrowing the passage in the core tube.  The combination greatly reduces hydraulic pressure transmitted to the caliper, reducing braking performance."

The statement is all assumption! I don't know what the inner material is made from nor do you! Do you know it is not PTFE? I don't!  And the remark about the absorbing brake fluids and swelling is way off base. It would never meet DOT specifications if what you say is true.
The statement about reduced interior diameter and swelling lines reducing hydraulic pressure at the caliper is incorrect. Hydraulics is hydraulics. Pressure applied is pressure realized at all points in the system. The real world test is a good brake which is dependent upon factors, other than brake lines.

"These considerations are important before declaring OEM brake lines "forever" components, flexible brake line expansion "bunk", and performance increases with stainless braid lines "illusory"."

I will still stand by my statements, since and foremost is the fact that all Honda brake lines are DOT approved which means they pass every test, the same tests that the DOT approved aftermarket brake lines have to pass. They all pass the tests.  I wonder if you will find where the aftermarket brake line manufacturers recommend replacing their brake lines after a certain period of time has passed. I don't think you will! Nor does Honda!

"Every manufacturer of brake lines refers to expansion or swelling of flexible brake lines, as does every automotive site I looked at.  Either you are right and all of them are wrong, or all of them are right.  Assuming that all those sources are not victims of mass hypnosis, which of the two choices is most plausible?"

Well of course they do! They're trying to sell you something!  It's always "Ours is better because......", you fill in the blanks.  To be oblivious about the obvious machinations taken in the name of marketing a product is "denial"!

What I object to, is the associated hype that is promulgated by unknowing riders, couched in scare terms in an attempt to confuse the less informed riders to think their set-up is less safe, less reliable and hazardous when they ride.

I suppose there is one thing we can agree on and that is: solid steel brakes lines are the best transmission of hydraulic fluid. There is nothing equal nor better.

Like I said earlier, I don't mean to exacerbate the situation and once again thank you for the pics and the interest you have shown.

***

[Valkpilot]

I certainly hope we can continue the technical debate without it becoming an arguement.  I may need your advice on a clutch replacement!

Thanks for the pictures you have posted and I admit that I was incorrect about the Honda lines being steel braided lines. I guess what I object to most is all the hype about replacement lines being such a superior product to the Honda Oem and reports by riders regarding their amazing discovery when having replaced their Oem lines with something else.

I don't think anyone went overboard regarding their endorsement of replacement lines.  Much of the performance improvement has to do with the age of the lines being replaced, and replacement with OEM lines would have also yielded an improvement.

I mean to say that if you replace your lines with stainless braided lines because they add to the look you want for the bike, then say so! There's nothing wrong with that. But to declare a huge safety boost that you can feel is such bull and only is concocted to boost an ego and encourage envy and worst of all, sway the novice riders that they are riding second class equipment and push them to make the same type changes unnecessarily.

I didn't go to SS braided lines because they are pretty.  I did it because I needed new lines and SS braid does present a performance upgrade.  You can, if fact, feel the difference, and it is, in fact, measureable.  I certainly did not present an argument that the OEM lines are less safe.  You've lept to a lot of conclusions here regarding personal motivation that a) can't be substantiated, and 2) are inccorect, at least in my case.

Further, I reject some of your statements couched in absolute terms. I want you to know however I'm not trying to start an argument with you.

Ditto.

The statement is all assumption! I don't know what the inner material is made from nor do you! Do you know it is not PTFE? I don't!  

Ah, but it's not an assumption.  I worked for 20 years in engineering, manufacturing, and quality assurance for a company that manufactured communication and electrical wire and cable, which from a materials and manufacturing standpoint is essentially a hose-making operation.  We extruded everything from irradiated rubber to flexible PVC to polypropylene to polyethylene to semi-rigid PVC to FEP.  I know the difference between PTFE and whatever flexible material is in the core of an OEM brake line.  The flexible material could be any number of things, engineered to be resistant to brake fluid, but not impervious to it over time.  By the way, the reason the OEM lines are black is because they are pigmented with carbon black to forestall degradation due to UV exposure.

And the remark about the absorbing brake fluids and swelling is way off base. It would never meet DOT specifications if what you say is true.

I disagree.  Modern materials are certainly better in this regard than say, 30 years ago, but I've personally observed brake lines in this condition.  And I'll reiterate, that initial compliance with DOT standards does not preclude degradation over time.

The statement about reduced interior diameter and swelling lines reducing hydraulic pressure at the caliper is incorrect. Hydraulics is hydraulics. Pressure applied is pressure realized at all points in the system. The real world test is a good brake which is dependent upon factors, other than brake lines.

Yes, but the pressure applied is intended to move specific volume of fluid with a goal of physical movement of the caliper piston.  The expansion that occurs with flexible lines (minimal when new, worsening over time) increases the volume of the line.  A 5% expansion in diameter results in a 10% increase in the volume of the line.  If 10% of the fluid is busy expanding the walls of the line, it's not moving the piston.

I will still stand by my statements, since and foremost is the fact that all Honda brake lines are DOT approved which means they pass every test, the same tests that the DOT approved aftermarket brake lines have to pass. They all pass the tests.  I wonder if you will find where the aftermarket brake line manufacturers recommend replacing their brake lines after a certain period of time has passed. I don't think you will! Nor does Honda!

I don't disagree with you regarding adherence to DOT performance standards.  But performance when new is not the same as performance after 12 years.  You're also correct that Honda doesn't have a recommended replacement interval that I've seen.  Instead, they recommend inspecting for cracks and leaks resulting from cracks.  Sounds like they recognize that their lines degrade over time.

Well of course they do! They're trying to sell you something!  It's always "Ours is better because......", you fill in the blanks.  To be oblivious about the obvious machinations taken in the name of marketing a product is "denial"!

Taking that into account, I cannot find a single source that refutes that flexible brake lines expand and that the expansion and degradation gets worse over time.  Instead, I find the opposite.

What I object to, is the associated hype that is promulgated by unknowing riders, couched in scare terms in an attempt to confuse the less informed riders to think their set-up is less safe, less reliable and hazardous when they ride.

I'm not sure how you arrived at this conclusion.  One, I don't consider myself an unknowing rider.  Two, there's nothing in this thread that attempts to scare or confuse anyone.

I suppose there is one thing we can agree on and that is: solid steel brakes lines are the best transmission of hydraulic fluid. There is nothing equal nor better.

100% right.  So logically, the more ridigity you can incorporate in a line that is not rigid steel tube, the better the performance.  SS braided lines, through a more ridgid core tube along with the braid material and coverage, accomplishes this better than a flexible line will.

I guess, that's my real point.  By design, OEM lines are good, by construction SS braid better, inherently, rigid steel lines best but not suitable for our application.

Like I said earlier, I don't mean to exacerbate the situation and once again thank you for the pics and the interest you have shown.

I hope you take my response in the spirit it's offered -- a technical debate so that we all avoid providing incorrect info.

[BamaDrifter64]

Wow...is this an oil thread????   

Dave

[Valkpilot]

Wow...is this an oil thread????   

Dave

Not yet, but be careful what you wish for.

[upjeeper]

I'm also a mechanical engineer working in a quality role for my current career position. As an engineer I'd really like to see some tangible evidence either way.

This is the best I could find

http://autospeed.com/cms/title_Braided-Brake-Lines/A_2679/article.html

synopsis is "a braided steel brake line does give less expansion under pressure than a rubber hose - but the margin is extremely small"
I don't know how many points along the lines were tested. It would be one thing to assume uniform expansion, but I don't know if that's realistic.

[Valkpilot]

I'm also a mechanical engineer working in a quality role for my current career position. As an engineer I'd really like to see some tangible evidence either way.

This is the best I could find

http://autospeed.com/cms/title_Braided-Brake-Lines/A_2679/article.html

synopsis is "a braided steel brake line does give less expansion under pressure than a rubber hose - but the margin is extremely small"
I don't know how many points along the lines were tested. It would be one thing to assume uniform expansion, but I don't know if that's realistic.

I'm glad you posted that.  I found it a couple of days ago, then couldn't relocate it.  It's interesting, but I don't think it carries the testing as far as it could.  For one thing, it doesn't relate the expansion to line volume increase, which is what really concerns us.  When taking the volume increase into account, the results might be considered more significant.

[Ricky-D]

I certainly agree that the expansion of the line when related to volume is the important factor here.

That last article (posted by upjeeper) sure is a help to clear up any questions and I expect it's pretty accurate!

Anyway, I guess the main point in this discussion is how the brake system feels and I think this is a very subjective area.

As long as there is enough brake to allow the total stopping (like skidding) of the wheel, well, that's Ok for me!
If, on the other hand you must pump the brake, you're in bad trouble.

Whether the brake stops the wheel at the beginning of the stroke or further on in the stroke,,, I know is affected by the hose as well as other things. Of course, I know that stopping at the end of the brake travel is a very dangerous situation.

I am feeling that discussion regarding minutia of this brake line is lasting far longer that I anticipated and I really want out, so this is going to be my last post on this thread.

***

[Valkpilot]

I certainly agree that the expansion of the line when related to volume is the important factor here.

That last article (posted by upjeeper) sure is a help to clear up any questions and I expect it's pretty accurate!

Anyway, I guess the main point in this discussion is how the brake system feels and I think this is a very subjective area.

As long as there is enough brake to allow the total stopping (like skidding) of the wheel, well, that's Ok for me!
If, on the other hand you must pump the brake, you're in bad trouble.

Whether the brake stops the wheel at the beginning of the stroke or further on in the stroke,,, I know is affected by the hose as well as other things. Of course, I know that stopping at the end of the brake travel is a very dangerous situation.

I am feeling that discussion regarding minutia of this brake line is lasting far longer that I anticipated and I really want out, so this is going to be my last post on this thread.

***

Agreed.

[98valk]

Braided Steel Brake Lines
Braided steel brake lines are popular with many people.
The braided steel is there only for protection from heat and impact - it adds nothing to the braking performance.
 However, the hydraulic lines inside the braided steel are of higher quality than the factory parts, and typically offer better braking feel and usually near or zero expansion. every race team out there either mc or auto use braided steel lines.
The interior line is teflon tubing.

http://www.spieglerusa.com/cfm/brakelines.cfm

When I went to braided lines on the front I also went to synthetic brake fluid. major difference in brake feel and stopping. I feel for the street one should use stock hoses for the rear. when the rear brake feels mushy all the time even after a fresh fluid change its time for new hoses.

[Disco]

Great exchange of information here! 

When I went to braided lines on the front I also went to synthetic brake fluid. major difference in brake feel and stopping.

OK, I'm trying to figure this one out and can't.  I'm not a hydraulics expert, but it would seem to me that, if all the components are operating correctly, any liquid would feel the same and any other benefit(s) would show up in other places.  I can't think of a compressible liquid. 

I feel for the street one should use stock hoses for the rear.

Why's that? 

[98valk]

Great exchange of information here! 

When I went to braided lines on the front I also went to synthetic brake fluid. major difference in brake feel and stopping.

OK, I'm trying to figure this one out and can't.  I'm not a hydraulics expert, but it would seem to me that, if all the components are operating correctly, any liquid would feel the same and any other benefit(s) would show up in other places.  I can't think of a compressible liquid. 

I feel for the street one should use stock hoses for the rear.

Why's that? 

My understanding is that because of a fluids different densities the compression difference can be measureable under different pressures. but generally it is so small it is just states fluids cannot be compressed. I'm sure someone with heavy equipment experience will chime if if they ever noticed a difference using different hydralic fluids. I used valvoline syntech and also noticed a difference in breaking feel when added to my truck with oem lines. So is there different densities btwn the brake fluids, I don't know except for the performance difference I have experienced. were mine on the bike from mostly the SS lines, probably and the truck new fluid verses old fluid mixed with water most likely. water and brake fluid there goes the different fluid densities again.
MHO on the rear brake line is less chance of lock up in a panic stop, more easliy controlled. Much less pedal feel through a boot than one has bare handed or with gloves. The valkyrie rear brake is fantastic to control I don't want to change it.

[hubcapsc]

On the OEM front there's that little piece of solid Tee, the rest is hose... On the OEM rear, it's mostly a solid metal tube, just a little hose on each end.

Maybe that's why it would be worth it to go braided SS on the front, or be particular about keeping the front OEM hoses fresh, while being
perfectly happy with OEM rear.

I rebuild my calipers with each pad change (not hard) and probably have 13 year old OEM hoses. I was real happy with the feel of
an emergency stop I had to make recently. I have a new OEM rear set of hoses, and will probably change out front and rear hoses with OEM on
some not-too-distant-future maintenance shot.

Aesthetically (and that's not what it is all about when it comes to brakes) I like the black OEM hoses 

-Mike

[Jersey]

I'm not an engineer, but have experienced the tendency for aged rubber lines to lock up the brakes when initially pressed.  My understanding is that an aged line will expand upon initial pressure then contract back, which then increases the pressure - leading to locking the brake.  After replacing lines that do this with new lines, I've noticed it doesn't happen anymore. 

As far as SS vs others, I do feel more secure using a SS wrapped line as I think it is more resilient to getting nicked or weakening over time... just my preference.

[Gryphon Rider]

What someone needs to do is compare brake lever travel for two Valkyries, one with SS hoses and one with OEM, hopefully both bikes with their hoses of the same age.  Also find two bikes with new and old OEM hoses to compare.  Years ago, when I was riding a GS850L, I read somewhere that brake hoses should be replaced every X years, an my bike was well past X years old.  I wrapped my hand around the brake hose, then squeezed the lever.  I could feel the hose expanding.  Never did change the hoses, though.  Maybe some year I'll change the hoses on my Valkyrie, or suggest that whoever inherits it do it.

[Ken aka Oil Burner]

Holy thread resurrection! 7 and 1/2 years. Just proves that some things will never be settled. Did someone say oil thread somewhere in the comments?...

[Glaserbeam]

Before getting my Valk two years ago I had an '81 CBX (bought new in '89).  Fifteen years in, I replaced the stock brake hoses with steel braided hoses (with nylon-ish inner core).  The positive:  much better braking feel, as if the stock hoses had been expanding under pressure.  The negative:  ten years later, likely due to flexing of the hose from fork travel, one of the twin front brake hoses (the inner core) broke where it joined the end fitting, where attached to the splitter under the steering head, while I was riding downhill toward a red light.  Lost all front braking; couldn't stop with the rear brake only; ran the light and it was a miracle I wasn't hit by any cars going either direction through the intersection.  Felt like the scene when Eddie Murphy runs across a highway in Bowfinger.  Now I feel that steel braided hoses might be "too rigid."  Or, maybe any type of brake hose needs to be replaced on a regular basis.