Hello all, I was 50 miles from home on a trip to Germany when my front brake started to have more free play at the lever and then soon after there was no front braking at all. A cursory look the next day revealed that brake fluid is coming out from between the left pipe and the bolt that clamps it in place on the right caliper:



I have tried nipping up the bolt but it doesn't seem to help at all, and have undone the bolt and pulled out the pipe but can't see anything wrong. Do they spring a leak here sometimes? Shall I just chop the pointy end off the pipe and try and mushroom it again? Or try and fit a nice bit of flexy brake pipe, probably routed over the mudguard?

New pipe in my book, brakes are brakes especially front brakes. Sorry to hear of your brake hassle, you did well to get back as you did.

I haven't heard of anything that is a known problem but being as brakes are sort of essential don't try to fix it yourself unless you have the right tools. Use a new line and new fittings.

Before you do anything else, put some more fluid in the system and then clean that area until it is spotless. Now carefully apply pressure and check for the exact position of the leak. I have seen a P08 caliper crack at that point because of corrosion between the hydraulic pipe fitting and the cast ally of the caliper.

You didn't happen to put a new front tyre on recently? ? ?

Dai wrote:Before you do anything else, put some more fluid in the system and then clean that area until it is spotless. Now carefully apply pressure and check for the exact position of the leak. I have seen a P08 caliper crack at that point because of corrosion between the hydraulic pipe fitting and the cast ally of the caliper.

Fluid spews out between the pipe and the bolt, nowhere else. I'd love to check the condition of the pipe to see if it is cracked but the bend is too close and severe to be able to move the bolt down along the pipe and have a look.

92KK - A new tyre went on 2 weeks/2500 miles ago, the pipe sure takes a battering during that process. I think we're on the same wavelength here.. I know a guy who makes braided hose, I'll see if he can make a nice bridge pipe for me. I don't like the solid pipe between the calipers anyway, it's awkward to work with and has the ability to crack during routine maintenance like wheel/tyre changes. Also 50 miles without a front brake is nothing, last year I had to ride my TRX850 back from near Trier in Germany to Leicester with no front brake as the seals in the master cylinder gave up! I dislike brakes somewhat

When you do get round to replacing the pipe I'd consider using copper, its easier to work with (softer)  and doesn't corrode as much.
You can pick up pipe flaring tools cheaply enough and after a few practice goes you can become a dab-hand at doing the job.
I've found that and coil of copper and a selection of fitments is a well worth addition to the workshop.

Sound advice from postman....

Is copper strong enough to take the strain while the calipers are being messed about with? They're not light items..

Copper is not strong. I have the brake pipe through the down tube and the flexible hoses. Easier to get wheel out.

I'm in agreement with Olaf. For the last X years any bike I've had with hard pipes has had them replaced pretty quickly with braided hose. As well as improving braking, it makes life a lot easier when taking the wheels out. And that included getting shot of that terrible pipe through the headstock on the K!!! (having to dismantle the hydraulic system just to grease the headstock bearings. Whoever heard of such a thing grumble grumble grumble).

Never ever ever use copper on brake lines. It WILL work harden and crack, then you are right back to square one if you notice that you have no brakes at a convenient time.

+ 1 for what Rick said.  It is also a good conductor of heat and I doubt copper tubing is rated to the same pressure as stainless, etc. 

Your life is worth more than saving a few pennies/cents. 

TacKler wrote: I doubt copper tubing is rated to the same pressure as stainless, etc. 

I would imagine your little rubber seals and the original rubber piping and your rusty steel piping would give way before copper.
If you realy are worried about work hardening go for a cupro-nickel pipe (kunifer), a bit harder to work with than copper though.

Back to this, does anyone know of a supplier of a braided hose that replaces this metal pipe? I've checked ebay, the three main BMW parts places here in the UK and Venhill but there's not a sniff of one, they all want to sell me a hose to each caliper setup which I don't really need. Otherwise I'll bite the bullet and buy another pipe for about £25, I don't have the equipment for bending steel pipe.

venhill will make you custom braided hoses

Pipe between calipers, Motobins Part No.21891, £ 19,20.

I've seen them, but would like to replace the silly solid line with a flexible one. Venhill will cost a small fortune and there's no guaranteeing it'll fit properly in the end. Just checked Goodridge's site too, nothing doing.

Bizarre that these don't exist, given the way a snazzy bit of pipe could be routed over the mudguard.

These people supply Venhill hoses at a reasonable price.........but, of course, you'd need some adaptors for the ends.

http://www.ebay.co.uk/itm/Custom-Stainless-steel-braided-brake-lines-between-100mm-800mm-VENHILL-/201167170190?pt=UK_Motorcycle_Parts_13&hash=item2ed67f6a8e

Paul.

Buy the bits from Venhill and make your own. I'm serious. I haven't bought a made-for-the-job brake pipe in almost thirty years.

[Edit] Just followed Paul's link - that's the guy I've bought my last three lots of fittings and pipes from. If you can stomach the price, buy stainless steel fittings instead of chromed steel. They'll look pretty for a hell of a lot longer.

I would be inclined to take the opportunity and put separate lines from the top and get rid of that PITA cross over tube which makes for very difficult.

I was looking at that crossover tube recently too and knowing the stresses when you take out a front wheel there is no way I would have it. We might not like the brake line down through the steering stem but it is only affected when you need to get at the head bearings and that's so infrequent its time to change brake fluids anyway. The flexibles from there don't hinder removing the wheel. But on ABS models I think its a little more tricky. Either way I would not feel comfortable having a rigid pipe there and would go down the road of making a flexible connector pipe to allow the wheel to be removed without a risk to the brakes.

Why not give these guys a shout, they're in Leicester. Their website says they make pipes and hoses to your spec or pattern. Five minutes of Googling found them. 

http://www.bondingandreline.co.uk/contact-us

As Avenger GT says...
Lots of braided hose supplyers
THESE will make up just what you want

That is very interesting, I'll try and give the people in Leicester a shout if I ever get the time to go see them. I already have a braided hose coming from the solid ABS pipeness down to the right caliper and don't feel any need to replace it, I'd just like a hose to go from right to left caliper.. The ABS doesn't look to make it any more difficult but I've never seen a non-ABS model to compare it to.

If these custom-hose making people want too much money (more than £25) I'll be making my own, sod 'em! Cheers all!

After far too much umming, aahing and flat out denial I decided some heated grips and a fairing would be nice during a trip to a bike show. I bought a steel pipe from Moto Bins thinking it's a bit rubbish but at least it'll bolt straight on and the bike will be working again in a couple of hours. Well, it did eventually go on but I am quite baffled because it's a very different shape from the old pipe and the mudguard no longer fits around the new pipe. My bike being an '89 SE has a fork brace and hence a two piece mudguard, and I think this is causing much confusion.. Time for some pics in the vain hope someone can tell me just how much of a pillock I'm being.

The new pipe, fitting perfectly:



The rear section of the mudguard, there is not enough cut out of the right side to allow the pipe to fit:





The old pipe, much flatter/nearer the tyre and didn't even try to fit between the brackety holdy bits on the inside of the mudguard, it fitted inside of those:



Is the pipe non original? Is the mudguard the wrong one? Is a braided hose to each caliper the only realistic way to go now? Please help

Hold on, looking at these pics in the post preview I probably need to put the pipe on the other way around, even though the old pipe was this way round (as I've fitted the new one). Will that fix my problem or is it still all wrong?

It probably is for the one piece front guard.

RicK G wrote:It probably is for the one piece front guard.

The one for the one piece mudguard have a different part number.
But it could also be that they have mixed up the part numbers at Motobins.

I haven't seen a link pipe that looks like the one I have taken off, to me it looks like it has been made up. It is also possible that the mudguard is not correct, it is a replacement and doesn't seem to fit very well at all. I'm quite glad about the silence, it must mean this is as baffling to others as it is to me!

What I really don't understand is if I turn the pipe around then it won't fit in the pockets of the rear half of the mudguard at all, so what are they for?

Edit - The pipe is actually from Motorworks, part BRA10076 which can be seen here. Their list of brake hoses for K100s is here, I can't see any other metal bridging pipes anywhere on any of the UK supplier's sites. Searching the part number 34322310076 as is given by realoem for my model of bike takes me to the same hose as the one I've bought. Curious! Realoem also provides part number 34321458402 which has perhaps been superceded, but I can't find any of those with a quick search.

I would guess you did mount it correct the first time, as the genuine pipe seems
to have a clamp and a small screw which I would guess should be mounted to
the fork bridge/stabiliser.......or is this clamp for the wire to the ABS sensor?




EDIT: Then it was wrong info in a previous post as the the BRA 10076 is for
the one piece mudguard.........as Rick said.

I would be using separate hoses because of the problems that come with bleeding and the cross over tube.

Snod Blatter wrote: Curious! Realoem also provides part number 34321458402 which has perhaps been superceded, but I can't find any of those with a quick search.

That's the one you need.........which is the same the one I earlier mentioned with the Motobins part number.

Inge K. wrote:That's the one you need.........which is the same the one I earlier mentioned with the Motobins part number.

So it is, it's more rounded and the bends aren't the same both sides. I think this is the winner!

As an aside I had no trouble bleeding through this new pipe, it was much easier than many other normal setups I've had the pleasure of bleeding