URGENT: Brakes. Help yourselves

[rip]

Saska,

Not all of us who have upgraded the fronts have also upgraded the rears.

I've tried stopping both cars with just hand brake -- HiSpecs all-round on one and OEM on the other.
Both stopped just fine.

I'm sure that those of us who have upgraded brakes did so without thinking that doing so might actually compromise our safety, and that while new brakes might be more effective, they might also be less dependable. We all need to know that when we push that pedal and mean it, we're going to f*cking stop, not that we might either:

a) stop really smartly (much better than with stock brakes)
or b) not stop at all.

I don't believe the issue is wholly related to upgraded brakes. Admitedly, they will re-route the hose, but the issue is that there is no securing clip fitted to the hose & the same would be true if you still had OEM calipers fitted. With no clip, the tendency is to believe that "If one was needed, it would be fitted". The reality is that the hose fitter should manufacture their own clip or tie-up.

[dapinky]

I don't believe the issue is wholly related to upgraded brakes. Admitedly, they will re-route the hose, but the issue is that there is no securing clip fitted to the hose & the same would be true if you still had OEM calipers fitted. With no clip, the tendency is to believe that "If one was needed, it would be fitted". The reality is that the hose fitter should manufacture their own clip or tie-up.

Yep - the same issue is present on the original calipers with SS hoses (I used Goodridge ones)......

....admittedly, i fitted them myself, and fabricated (read 'bodged up') a system to hold it all in an appropriate possition without really thinking too much about it - it's not a lot different than on many other cars I've worked on.

The 'problem' appears to be when the hoses are fitted by someone (owner, amateur or pro mechanic) who expects it to be a straight swap 'plug and play' system, and doesn't fully examine the routing after fitting.......

....this would have just as much potential of failure on a Mondeo, Clio, Evo or Merc (pick your own vehicle!!!) in the same circumstances......

...having built up many competion cars, some with little suspension travel (track use) and others with lots (forest rally), i have learned that correct routing of everything is important!


There are enough instructions on the forum to ensure that people CAN do it right, and i agree that it never hurts to re-itterate safety issues - however, i just want to re-emphasise that it is NOT an issue with the brake caliper upgrades, or any of the people who have organised the engineering/purchase of them - it is a characteristic of the flexible hoses, which need to be correctly fitted.

[Alan_C]

.....however, i just want to re-emphasise that it is NOT an issue with the brake caliper upgrades, or any of the people who have organised the engineering/purchase of them - it is a characteristic of the flexible hoses, which need to be correctly fitted.

I've just checked my Hi Spec upgraded SE, it has the original 15 inch wheels and the HEL braided hoses. Using the 15 inch wheels means there is less tollerance in the hose routing than on an S2 with 16 inch wheels. I very carefully routed the hoses when I installed them, checked with the car's full weight on the suspension from lock to lock and even had someone bounce the suspension to ensure the hoses didn't touch the wheels. I used the supplied hose clips with cable ties on them, it seemed obvious this was required. It wasn't the easiest job to do, you certainly can't just slap them on any old fashion, but when fitting any flexible brake hose you'd check it wasn't fouling anything, especially something that could chafe and cause a rupture. There's no sign of my hoses having chafed anything to date. But please, if you have changed your hoses, or had them changed, check them, just to be sure. As Dave said, there is NO issue with these kits when fitted correctly, all the parts DO fit, and are all fit for purpose.

[Jackonicko]

I hear what you're saying, and don't disagree, but if the person who fitted mine could get it wrong, so could anyone.

[ashm]

As Dave said, there is NO issue with these kits when fitted correctly, all the parts DO fit, and are all fit for purpose.

I also agree with this; I'm very confident that once I got my HEL lines correctly routed they were safe and secure, and a good improvement on the OE hoses.
Of course, even though I think the kit is good, I also think it can be very tricky to fit it correctly. Therefore it's likely that there's room for improvement to make it easier to route the hoses safely. I know there will soon be experiments to investigate this, and I'm sure the results will find their way back onto the forum so we can all benefit.

On the other hand, the potential issue with the BMC (if it turns out that there is one) is not due to difficulty in fitting, but a fundamental problem with the system and concerns me somewhat.

Adam

[RayD]

Is it practical to have the final hose made in two parts such that the joint coincides with the existing bracket and could be secured firmly in place – metal to metal?

Then there’s the position and direction of the new calliper inlet ... if the second part of the new two piece hose started at the existing bracket is it possible to get the steering movement taking place in the centre of the hose as it does on the original?

Is it possible to get the hose not to reach the wheel under any circumstances?

On the subject of the dual master cylinder system failing ...

Has anyone seen it work on the standard set up?

Could it be related to pedal travel with the increased calliper capacity?

If the dual system definitely doesn’t work with upgraded brakes I wonder if it's worth changing the pipes over to front and rear instead of diagonal ... at least with a rear pipe failure the chances of stopping would increase.

Ray

[bobbrown]

Is it practical to have the final hose made in two parts such that the joint coincides with the existing bracket and could be secured firmly in place – metal to metal?

This creates two problems, to get the lengths correct for OEM, upgrades on 15" and 16" rims and adds to the cost as it will make the hose set 8 pieces not 6 so will add 33% to the cost and I do not see any difference than locking the centre mount.

Then there’s the position and direction of the new calliper inlet ... if the second part of the new two piece hose started at the existing bracket is it possible to get the steering movement taking place in the centre of the hose as it does on the original?

I do not understand!
Both Hi-spec and Wilwood calipers have their fluid port in the middle of the caliper in much the same position as the OEM caliper the only difference being they are further out due to the discs being bigger in diameter. Also the hose follows in the most part the route the original hose follows.

Is it possible to get the hose not to reach the wheel under any circumstances?

Simple answer NO, as you can even get the standard rubber hose to foul on the wheel if the hose is positioned incorrectly.

On the subject of the dual master cylinder system failing ...

Has anyone seen it work on the standard set up?

Could it be related to pedal travel with the increased calliper capacity?

If the dual system definitely doesn’t work with upgraded brakes I wonder if it's worth changing the pipes over to front and rear instead of diagonal ... at least with a rear pipe failure the chances of stopping would increase.

I do not think the fact that the brakes have been upgrade makes that much difference as the fluid requirement has not been increased by any significant amount and a Hi Spec upgrade would only increase the fluid requirement by 10% and that should be well with in the range of the current setup assuming there is enough pedal travel to allow the one of the pistons to hit the stop in the tandem master cylinder so the other one can still work and this may or may not be the case with the OEM setup..
The only upgrade that had any real pedal travel issues were the ones with the incorrect caliper part number and vastly oversized pistons at 44+ mm
It is easy to calculate, the OEM caliper has one piston 52mm diameter and the Hi-spec conversion has 4 pistons 38.6mm diameter.

[RayD]

Thanks Bob,

Is it practical to have the final hose made in two parts such that the joint coincides with the existing bracket and could be secured firmly in place – metal to metal?

This creates two problems, to get the lengths correct for OEM, upgrades on 15" and 16" rims and adds to the cost as it will make the hose set 8 pieces not 6 so will add 33% to the cost and I do not see any difference (other?) than locking the centre mount.

I imagine most people would prefer to pay 33% more for the hoses if it did away with the possibility of them ever catching the wheel.

There would be no difference other than locking the centre mount, but it would at least be locked in position. The final piece - if the visual appearance of the original hose is anything to go by - would not touch the wheel under any circumstances, providing it was the right length and fitted in a vertical plane.

Then there’s the position and direction of the new calliper inlet ... if the second part of the new two piece hose started at the existing bracket is it possible to get the steering movement taking place in the centre of the hose as it does on the original?

I do not understand!

Sorry, I was trying to get the point over that the position of the port on the calliper and direction the pipe approaches it from is an important ingredient in avoiding contact. And ... that the movement in the hose wants to be taking place centrally to lessen the strain on the connections, and vertically to keep it away from the wheel

Both Hi-spec and Wilwood calipers have their fluid port in the middle of the caliper in much the same position as the OEM caliper the only difference being they are further out due to the discs being bigger in diameter. Also the hose follows in the most part the route the original hose follows.

That’s good; at least it shouldn’t be too much of a problem to overcome.

Is it possible to get the hose not to reach the wheel under any circumstances?

Simple answer NO, as you can even get the standard rubber hose to foul on the wheel if the hose is positioned incorrectly.

It doesn’t look as if the hose is long enough to touch the wheel under any circumstances on mine – but I have standard callipers and 16” wheels

On the subject of the dual master cylinder system failing ...

Has anyone seen it work on the standard set up?

Could it be related to pedal travel with the increased calliper capacity?

If the dual system definitely doesn’t work with upgraded brakes I wonder if it's worth changing the pipes over to front and rear instead of diagonal ... at least with a rear pipe failure the chances of stopping would increase.

I do not think the fact that the brakes have been upgrade makes that much difference as the fluid requirement has not been increased by any significant amount and a Hi Spec upgrade would only increase the fluid requirement by 10% and that should be well with in the range of the current setup assuming there is enough pedal travel to allow the one of the pistons to hit the stop in the tandem master cylinder so the other one can still work and this may or may not be the case with the OEM setup..
The only upgrade that had any real pedal travel issues were the ones with the incorrect caliper part number and vastly oversized pistons at 44+ mm
It is easy to calculate, the OEM caliper has one piston 52mm diameter and the Hi-spec conversion has 4 pistons 38.6mm diameter.

While I kindly entertained the idea earlier, it seems unlikely they would send them out of the factory without dual circuit brakes working.

How did you arrive at the 10% extra fluid requirement?

Ray

[MPx]

I've checked mine and see no damage.....but then I see no potential for damage either. Its an S2 so 16" wheels, but where exactly would the pipe touch the wheel if I'd done it wrong??

[RayD]

... but where exactly would the pipe touch the wheel if I'd done it wrong??

If the spare hose passed through whatever fixing you have behind the ARB the vertical hose leaving the banjo may touch the wheel. If the wheel is smaller it would reach it sooner.

The originals set off upwards rather than downwards but it doesn’t appear to make a difference as long as they are in a vertical plane.

Ray

[Candles]

but where exactly would the pipe touch the wheel?

After successive applications of full right lock (in the case of your pictures) the brake hose would pull through the intermediate mounting where your yellow hose label is (bottom picture). The loop from the brake caliper union would then be so long that came very close to the wheel, and if fitted, touched the balance weights glued on there.

[rip]

While I kindly entertained the idea earlier, it seems unlikely they would send them out of the factory without dual circuit brakes working.

I'm not so sure the split system works at all & Lotus completed Elans with steel rear sliders then only recalled the US ones after a lawsuit about it.

Back when I had stock calipers, one of my rear pipes ruptured. Because the damaged section was very small, I lost only a small amount of fluid & it took several pumps of the pedal before the low level warning light came on.

If one of the front brakes was working better than the other (which should happen in the case of a diagonally-split system failure), I would expect the car to pull to one side. This was not the case: braking was virtually non-existent but still balanced.

[MPx]

but where exactly would the pipe touch the wheel?

After successive applications of full right lock (in the case of your pictures) the brake hose would pull through the intermediate mounting where your yellow hose label is (bottom picture). The loop from the brake caliper union would then be so long that came very close to the wheel, and if fitted, touched the balance weights glued on there.

Aahh thanks for that. If that's the issue then I think downward exit on Bob's kit will be fine. There is very little slack in the hose above (or below) the centre clip where the yellow label is, so not much potential for pulling through either way. I did nothing in prep for the pictures so that is where the pipes naturally rest following normal (and track) use. When I first fitted them with the car jacked and the hubs dangling I angled it differently because I didn't think they were long enough and was worried about tension on the pipe if the wheels ever reached the bottom of their travel. The angles were reset to vertically down by the garage when the car was MOT'd because the tester was concerned about something with the routing. Maybe the very issue raised here(!), so looks like I've been lucky.

[rip]

The angles were reset to vertically down by the garage when the car was MOT'd because the tester was concerned about something with the routing. Maybe the very issue raised here(!), so looks like I've been lucky.

Sounds like you've found a good MOT tester. I'd be much more willing to go back there than to one who saved me money by turning a blind eye to something.

[Jackonicko]

I imagine most people would prefer to pay 33% more for the hoses if it did away with the possibility of them ever catching the wheel.

DING!

Orientating the hose vertically is also crucial. I would suggest that the calipers need a mod to ensure this (even if only an engraved guide on the rear face) - or 90° Banjos to take the hose straight out from the caliper.

I've now had TWO different highly professional, highly experienced, rightly widely respected expert engineers f*ck up the installation of braided hoses on the HiSpecs badly enough that they have rubbed on the wheel. The first time it resulted in catastrophic brake loss which could easily HAVE KILLED ME. The second time I picked it up before the plastic sleeve was completely worn through.

I heard the N/S hose rubbing at low speed today...... but after hundreds of miles of it having done so.

I would suggest that NO set of HiSpecs should go out without comprehensive fitting instructions that explicitly warn against this.

I am becoming quite irate about this......

[RayD]

I understand your frustration Jon,

Any proposed solutions want considering by everyone concerned.

People need encouraging to ask questions about safety related issues without being frowned upon.

Ray

[ashm]

I would suggest that NO set of HiSpecs should go out without comprehensive fitting instructions that explicitly warn against this.

I'd suggest that no set of _hoses_ should go out without such a warning. I still think you could easily have this problem with any calipers, it's really routing the hoses that you've got to be very careful about.

Adam

[DeeAitch]

Scary moment on Friday. Asked the MOT guy to check the rears after finally getting the Dorman calipers to feel OK.
Foot brake seemed same as before but OK, hand brake back to previous MOT OE standard, happy Bunny.
"Please try the foot brake one more time as I didn't get the numbers" - pedal went straight to the floor!
WTF say's I, hopped in and yes, pedal goes straight to the floor!
Big pool of fluid under the off side front. Closer inspection reveals big bulge in the braided hose. These are the ones supplied by SJ which have a tubular 'slider' on the wishbone support, better than the option provided on the Goodridge flexes, or so I thought.
6 years of sliding back and forth has worn thro' the braid and the inner Hose has now escaped it's constraint! Bluddy scary as this could easily have killed me only 10 mins previously whilst hard on the brakes from, ahem 70, before that nice slow roundabout on the A19
Dual circuit brakes? Bollecks!
Happened to have a set of Goodridge hoses as spares but these are almost impossible to fit safely as they have no central support worth talking about. First fit and they fouled the wheel rim (16"). Can't see how they could fit 15" wheels safely.
Have them fitted OK ish now with P Clips, spacers etc but really they should be ashamed to sell them like this. If you simply stuck them on as supplied they could be a death trap waiting to happen.
Not at all happy so I'll be on the blower to Lotus to see if the OE hoses are still available. Old ones lasted 15+ years so should safely see me into retirement
If you have braided hoses fitted please, please, inspect them. Any signs of wear to the braid change them - NOW!

[RayD]

Sorry to hear that Dave,

As you say, at least it happened at the test station.

I think I've mentioned it before but my brakes get more pressure applied during the MOT than at any time through the year ... by a long way.

Let us know how you go on in your search for the originals.

While you'll keep it in mind about fitting them vertically, it's worth mentioning again as a reminder to others.

Ray

[Brit-Car-Nut]

If you need the Lotus part number, it is A100J0025F

They are still active in the price guide at £16.54 + VAT each. Your local dealer can get them for you at this price.