Hi all.

Had 4x4 cossie front brakes on my escort untill recently a virtually new set of Hi spec 4 pot 330mm brakes came up at the right price.

Since fitting them i have a couple of issues that i dint have before. I have bled the brakes about 3-4 times now and i get a stream of micro bubbles at the front right caliper only. All the connections are tight with ptfe tape and there is no leaks anywhere including at the master cylinder, so i am baffled.

Also under braking the car judders like mad. Is it possible that the discs could be warped? Even though they are practically new and only came off a road car.

Any help would be highly appreciated.

 

Do you mean the bubbles are visible within a clear tube as you are bleeding the brakes? It could be dragging a bit of air through the threads on the bleed nipple?

Is the pedal pressure good when you have bled them, with no leaks or pedal sinking?

It does sound like the discs may be warped.

 

I have read Hi Spec are made in Japan, therefore don't have to meet the EU standards.

I know of someone who had them on his Cossy and they looked brand new but around one of the pistons was a bit of corrosion causing it to leak under pressure, not noticeable at idle.

New seal's didn't cure it so they were trash, maybe worth checking

 

Yes the bubbles are clearly visible through the tube on the bleed kit but there isnt much in the way of a spongy pedal and there is no leaks anywhere. I have tried bleeding the brakes with the bleed nipples in various stages of unscrew to see if i t was just dragging in air at the nipple but it doesnt seem that.

I am swaying more toward the discs being warped too because on top of the car juddering under braking the brakes feel as if they are on off on off in very quick succession. Are hi spec discs crap? Because these things are bloody brand new

 

Cheers mike i will take them off at the weekend and have a look at them. I could have been sold a dog here then :/

 

i've been looking at getting a set for my S2, glad I read this thread now

 

why are you using ptfe tape?
the banjo's use copper washers to seal
if you have a decent pedal but get air out when you bleed you might be undoing the nipple too much

 

I used ptfe where the braided line connects to the original metal pipe, and at the banjo bolt to try and solve the air issue.

As previously said i have tried bleeding the brakes with the nipples at various degree's or unscrew. As soon as its loose enough to allow flow there is air coming through.

 

I had that and I had mounted the calipers the wrong way up. I had the bleed nippled at the bottom DOH. I was never impressed by the brakes though and they had a lot of vibrations. I think the actual discs are the weak link.

 

I got the 283mm kit on my car they are spot on. No problems, No fitting instructions which was annoying as I had to play around with them until I found the perfect fitment.
The kit comes with EBC discs and pads, Never heard of them coming with their own though. Bought from Burton power.

 

I bought the same kit mark and mine judder like a coont . I did swap them for 4wd cossie set up so can't complain too much I guess . Looked into getting some bigger bells and rotors and brackets etc and hi spec wanted over £600 for the lot .

Thought that was a tad dear

 

Regarding the vibration, have you checked the torque of all the bolts mounting the bell to the disc? Know some of mine had worked lose (or probably not done right in first place) and when done right felt a hell of a lot better.

 

I never checked them tbh but I will now , good tip

 

Hi Spec had a name for being sub-rate crap back in the early 00's, and heard no end of complaints about them. The general consensus then was don't bother, as you'll end up buying twice, so just go for the dearer, but more proven, alternatives the first time.

No idea if they bucked their ideas up since then, but it was widely regarded as avoid, avoid, avoid....

 

Thanks everyone. The bolts do look quite rusty so i'll be on to hi spec to buy a new set and replace them at the correct torque settings. First that £16 solution, if that doesnt work new pads and discs at circa £200, if not that then new bells too. If none of those things work then i will be a deeply dissapointed and very much in trouble with the mrs man