29 replies to this topic

[Bobbins]

I’m in the process of assembling my front brakes, all new components swapping from 8.4” to the 7.5” “S” setup.

Previously the brakes were fitted with shields and I’ve already bought the 7.5” version shields with a view to replicate a fairly “standard” setup, although they’re currently somewhere in my parts stash and as yet I can’t find them, not untypical!

I’ve noticed some cars run without the shields which leads me to question what are the pros / cons of fitting them? My other weekend toy is a Caterham which doesn’t have shields, but being more open-wheeled it has substantially more, and more even air flowing over the brakes.

I should add that my driving style is certainly not brake heavy if that’s relevant. Any thoughts?

Stu.

[sonikk4]

Not fitted to my clubby when i converted from Drums to discs. Defo will never be fitting them either.

[Quinlan minor]

I prefer mine on and, since I started making my own tabs to bolt to the steering arm, I haven't had one fail.

[timmy850]

My only experience with the shields was a rock getting stuck between the disc and shield and making one heck of a squealing noise! When I built up my set I didn't bother with them 

[Bobbins]

Thank you for you comments. So why are they originally fitted? There must be some advantages?

[Quinlan minor]

Thank you for you comments. So why are they originally fitted? There must be some advantages?

They keep stray grease from the CV and Ball Joints from getting onto the discs, as well as keeping the discs drier in wet conditions avoiding brake lag, less of a problem on a show pony than on a regularly driven car.

[weef]

As you say manufacturers still fit brake back plates so they must offer something.

Maybe its down to asthetics, where the shield hides some suspension components and things look nicer when the wheel is removed, but I think its more than that.

The outboard face of the disc is protected somewhat from road debris by the wheel, whereas the inboard face, if no shield is present, is not.

The shield keeps road contamenants from the inboard disc face, prolonging both disc and pad wear and possibly providing better braking.

It also shields the suspension components fron the corrosive nature of the brake pad dust, just look at what brake dust does to wheelrims if not regularly cleaned off, making them cleaner and nicer to work on, and lets face it its a Mini we are talking about so suspension work is not unknown.

Really speaking over the years I have ran vehicles with and without shields and there appears to be noticable difference when everyday driving to braking effect, but as manufacturers still fit them there must be some good arguements for fitting them.

[mab01uk]

I think they are really water shields.....if you drive for some time on a very wet motorway journey for instance, sometimes you would rarely use your brakes if traffic is light but when you do sometimes the brakes don't bite as you expect them to, rather like when you are told to dry off your brakes after passing through a flood. It happened to me and comes as a bit of a shock when it happens....I now have disc shields fitted but down to choice if you fit or not but it pays to be aware and apply the brakes on long runs occasionally in wet weather.

If they were not needed car manufacturers would cut costs and not fit them.

Edited by mab01uk, 24 June 2024 - 10:14 PM.

[GT Jimmy]

I refitted mine just because they were there. There must be a reason to have them

[Lplus]

I was running without them but found that after a period of motorway running without braking, the first time I braked the mini pulled left hard, but if i braked again shortly after it braked square.  I reckon it was because the hot air from the rad was warming the left hand disc enough to make it more efficient until the first brake application warmed the rhs to match.  Fitting shields cured the problem.  Now it might be I am using pads which just happen to need a little warmth to make them bite well, but given the protection from water ( if I ever take it out in the rain...) it seemed worth doing.  The shields needed a bit of modification to fit round minisport 4 pot calipers.

[alpder]

I found that without them the brake lag due to spray on the disks was pretty nasty. Not the delay in braking itself, but the fact that each side would dry out and bite after a different amount of delay. So when needing to brake hard and suddenly, the car would pull very sharply and randomly to one side or the other. So much that you'd have to ease up on the brake or end up in the hedge or the oncoming traffic. Admittedly it happened only when there was substantial standing water and some cars aren't ever going to see weather like that. And at least half of my Mini driving miles are done with a 150kg trailer, which probably makes the car more sensitive to asymmetry. For me, shields are a PITA but I wouldn't be without them now.

[68+86auto]

I have had no problems with them installed.

[Cooperman]

Ever since I bought my first disc-braked Mini, exactly 60 years ago this week - a new 998 Cooper, I have removed the disc shields to improve brake cooling, eliminate a source of rusting components and prevent bits of grit from getting jammed between shield and disc.

They are really unnecessary.

[slidehammer]

I think if you want originality fit them, but if you do a lot of spirited driving and there is a chance of brake fade remove them, You will get more air flow over the disc. without them. Just for reference they are fitted on my Mini, but I am getting older and drive more sedately these days.

[mab01uk]

There is an interesting old thread on the Autosport forum linked below which as here, has some for and against and their reasons....however as said car manufacturers always eliminate cost where they can and therefore the reason given for safe braking performance in wet conditions is the most likely reason they are fitted as standard:-

https://forums.autos...-brake-shields/

Edited by mab01uk, 25 June 2024 - 02:37 PM.