Brake pad advice please.

[DJ.]

I need to replace the rear pads on my  S3 125 Roadsport with standard brakes. I have been generally happy with the brakes apart from a slightly long pedal after a particularly long track session at Goodwood. The pads squealed for a bit after that but otherwise they recovered ok.

The standard rear pads on the Caterham site are rather expensive and out of stock.

So after a lot of searching forums etc, I think I have found similar standard pads at Camskill : http://www.camskill.co.uk/m33b0s3341p25832/Mintex_Standard_Brake_Pads_-_MDB1287_-_Mintex_Standard_Brake_Pads_

Could someone confirm these are correct please?

Also, during my research I kept coming across the advice to swap the front pads to Mintex 1144 compound to both improve braking and move the balance to the front.

Is this a good idea? I've found these at Camskill: http://www.camskill.co.uk/m33b142s3402p27759/Mintex_Performance_Brake_Pads_Mintex_M1144_-_MGB533M1144_-_Mintex_Racing_Brake_Pads_/ZOOM99933

They seem very reasonably priced, so if you recommend them it would seem silly not to upgrade at the same time.

Thanks for your advice

Duncan

[Roadsport06]

Yes 533 at the front with spitfire callipers but as per Richard Price's advice: it will give you too much front bias so the uprated rear pads are needed too, the blue spot ones from Caterham. No idea what those ones are though.

My bias was terrible with the standard pads (rear was in danger of overtaking the front) and braking was poor. This change made a massive difference.

 

[Richard Price]

If you have a long pedal, then that is caused by fluid boil, not the pads.

swapping to a fluid with a higher boiling point will prevent the pedal going soft.

[DJ.]

Thanks for the comments, I'm not worried about the long pedal as I don't go on track much and it has been fine apart from one occasion.

 

So if I fit the sets of pads linked to, I will get too much front bias? Can anyone give me a link to the ideal rear pads?

 

I have found rears on the Caterham site that say to be used with upgraded front brakes, but surely just changing the front pads to Minted won't have as much effect as fitting 4 pot calipers.

 

 

[Richard Price]

DJ,

Standard brakes with 1144 pads work very well.

Big brakes won't actually stop the car any quicker. However, as they are larger and ventilated, they'll continue stopping the car time after time from high speed without fading. That said, standard brakes still work very well!

To stop the car quickly, you need both axles to be adding to the retardation as much as possible, therfore, it's important to retain reasonable balance.

Fitting Mintex MGB533M1144 pads in the front shifts the bias towards the front a little too much, and you can benefit from slightly better rears.

MGB533M1144's in the front, and the pads in the link below, work very well.

http://www.caterhamparts.co.uk/product.php?id_product=668

Don't be tempted to use MGB535M1144 pads. They have a greater area, and improve the fronts too much to retain any balance.

Likewise, don't be tempted to use 1144's in the back. You'll have way too much braking power from the back, making the car very unstable under hard braking, locking the rears way before the front.

 

 

[DJ.]

Thanks Richard, that is brilliant

I will do as you suggest.

 

[Martin J]

It's funny we all have different experiences with our brakes. I changed my fronts to the larger Mintex MGB535 & new solid discs at the same time. I noticed better more progressive braking & at the moment still have the original standard pads in the rear. In the past I had the rear locking up first with the standard fronts as they seemed to grab more.

I suppose the ideal answer is to fit a brake bias valve like the racers use. I assume this would mean holes in the floor & new brake lines though.

[Richard Price]

I suppose the ideal answer is to fit a brake bias valve like the racers use. I assume this would mean holes in the floor & new brake lines though.

Valves aren't really ideal at all.

Dual master cylinders and an adjustavle bias bar offer far more options, and take much of the experimentation out of pad choice, but take a bit more engineering....

The Caterham series racers don't use dual master cylinders because they aren't allowed to.  

[oldbutnotslow]

The standard rear pads on the Caterham site are rather expensive 

Please understand Duncan I am not having a go at you but  I find it very hard to understand cost being the main consideration in determining the two things that generally speaking stop you flying backward through the pearly gates backwards in a ball if fire

Brakes and tyres  

I want the very best of both. Yes try to get the best deal you can on the parts but I dont believe that you should stint on the quality.

1144's are an improvement on the standard pad but they are a long way from being the best out there.

If you want some professional advice may I suggest that you speak to John Freeth at Performance Braking on 01600 713 117

"After a 22 year career with Girling Ltd, John Freeth established Performance Braking as a continuation of the Girling dissolved UK racing department.

During his time at Girling, John was an experimental vehicle fitter, development engineer, test driver, racing department manager, technical sales representitive to Rover cars and the principle of friction material testing for volume car projects." He was also involved with the Thrust 2 land speed car.

From past experience he will be very happy to chat things through with you.

[TomB]

I though pt the well trodden standard brake path, was Mnte 1144 on the front and standard pads in the back (although I'm it sure what 'standard' is) - it it standard Sierra ? 

[DJ.]

I take your point about safety related items, but there is a difference between spending extra money to get extra performance and being over charged for a fairly standard product.

The standard rear pads from Caterham are £46.20, but a good brand (Mintex) alternative is only £14.20 from Camskill.

I have actually done as you suggest by spending a little more on the rear pads (£29.64 - interestingly less than they charge for the standard ones ) to get the uprated ones Richard suggested to go with the 1144 front pads.

Thanks to the knowledge given freely by a fellow member, I should have an improvement in braking, over my already pretty good standard brakes at quite a modest outlay

 

[Pendennis]

However, if your pedal is going long after a period of track time, your boiling the fluid because it has moisture content within. Unless you flush all the fluid clear with Virgin fluid you may as well give the money your intending to spend to charity!

Sorry Duncan! I had it happen to me twice this year during long races, very unsettling it was.

[Roadsport06]

Richard's point about the pedal travel should be taken on board too. Over time the boiling point of your brake fluid will drop, if it was a while ago then get it changed. Every two years is the recommended time interval, but I tend to do it each year as it is only a few quid a bottle.

[DJ.]

Thanks guys, don't worry the fluid was changed immediately after the track day.

It was a little under 2 years old. I always use a fresh unopened bottle too

 

It was an unusual circumstance, because I only do one track day a year at Goodwood. It was a hot day and due to a hold up we ended up getting a half hour session when normally it is only 20 minutes. It never felt dangerous, just by the end the pedal didn't feel as solid as it normally is. I just slowed a little and by the end of the cooling down lap it felt like normal.

[Martin J]

I plan to change my brake fluid at the next service in the Spring. This will be the third change in the seven years I have owned the car. What are the thoughts on replacing the clutch fluid? I never have & am reluctant to disturb the plastic bleed point on the plastic slave cylinder in case I break something.  

On the sigma the clutch slave cylinder is inside the bell housing so any problems will mean an engine out job.  

[DJ.]

I know what you mean Martin, I dread problems with that item

However, I changed my clutch fluid last winter and the fluid that came out was rather brown compared to the new fluid. I undid the plastic valve by hand (scratched arm/hand afterwards of course!) and just let the fuid drop through by gravity until it came out clear below

[oldbutnotslow]

Duncan

Make sure that you clean up the brake rotors properly before you fit any new / different pad material as the rotors become coated in a very thin layer of the current friction material which the new material won't remove. The result is that the new pads don't bed in properly and therefore you never achieve the full potential of the new material, Vigorous use of 80 grit production paper generally works. Don't worry about scratching the surface, It shows that you are doing it correctly.

 

Martin Its just the same sort of hygroscopic fluid but not subject to the heat cycles that brakes are.

It should be changed at least every 2 years.

The Sigma bleed can be a bugger to get at true but this should not prevent you from doing it. 

Put a tube on the nipple and unscrew in the normal way and allow it to drain into a tray. You will know when the nipple is fully open as the nipple wont turn any further. Simples!

[DJ.]

Thanks for the tip, I have loads of 80 grit

[7 wonders of the world]

a couple of points to be aware of:

Using the slightly larger pad area version on the standard pad will not make the fronts more powerfull, it will reduce the intial brake effect though as the larger area reduces the stileto heel effect.

A larger area will last longer and enable the brake to tolerate more heat - more material and greater mass.

Simply buying the same brand of pads will not ensure that yu are uding the same material, Ferodo make the same pad (using the same backplate) with a variety of differint materials to suit different applications from a 1.3 sierra to a Scorpio Cosworth, look at the pads and there will be an FF 1234 number the four digit number is the material number, I used to be able to get graphs for these, but sadly no more.

Balance bars are the ultimate yes but i a lightwieght car like a 7 a limiting valve can be used to good effect, as by careful safe testing you will be able to optimise braking under different load conditions,: driver only with 5 ltr of fuel for sprinting, two up full tank for road, etc naturally the later adds significant additional load to the rear end and so naturally it able to manage an increased braking load.

Once you've found the idea settings you cna simply swap from one to the other depending on usage.

  Worth spending time setting the M/C travel too as you can releave the system of a lot of free initial pedal travel giving you a reassuring pedal right at the top. 

[DJ.]

Update:

I fitted the Mintex MGB533M1144 pads  and the Caterham rear pads (for use with uprated front brakes) as suggested by Richard Price.

I've had a chance to bed them in and try them out on the road.

There is definitely more responsive braking compared with the standard pads, and I am now more than happy with the brake performance. A couple of extreme braking attempts on quiet roads with different surfaces have both resulted in front brake lock up, so I'm happy that the uprated Caterham rear pads are a good match with the 1144 fronts and aren't too powerful.

Obviously, I do not claim to be a great expert,but I've added this so anyone searching in the future can see that I am happy with the result

[John Cousins]

Reviewing brake pad options for my 2005 Roadsport with standard brakes - settled on Mintex MGB533M1144 pads for the front. Can I confirm that the Caterham pads they describe as: BRAKE PADS REAR - USE WITH 4 POT FRONT BRAKES - would be a good match?

[DJ.]

That's what I fitted, and my brakes are much improved over the standard pads.

I have now had a real emergency situation on the road which led to me locking one wheel and even with the uprated rear pads, it was still a front wheel that locked first.

Duncan

[John Cousins]

Thanks