30 replies to this topic

[dklawson]

Welcome!  You have listed your location as "Washington" but that could be "state" or "DC".  Where are you?  There are some other Mini owners in the DC area but at the moment I cannot think of their names.  If you are in Washington State, there is a fairly large owners group in Seattle.  Regardless, you may find it beneficial to have other local Mini owners look at your car and drive it so they can offer their comments. 

 

My car has the 7.5" disks and "standard" factory pads.  It stops quite well.  While the EBC pads have a good reputation, I have not used them.  I mainly read discussions concerning the Green pads mentioned by Wise Old Elf, I am not familiar with their other compounds.

[KernowCooper]

I had the new 7.5 disc setup and had exactly the same feeling in the pedal, the pedal pressure was very high, I fitted a servo as per the Innocenti standard fitment on a front/rear split and now the brakes are very effective.

 

See below details

Attached Files

•  Mini Innocenti Brake Layout.jpg   23.41K   64 downloads
•  Servo.jpg   34.69K   49 downloads

[sonikk4]

Sounds like it could be down to the pads not bedded in correctly.

I did the Cooper S conversion on my clubman and although some force is needed the brakes work really well. This is on the standard pads as supplied as well. ( no servo assistance either)

I did fit the slightly larger S master cylinder but other than that it's as per the conversion kit. I have now put on roughly 800 miles since installation and they work a treat.

There has been some debate about the pedal throw difference between drum brake pedals and later disc fitted brakes but to be honest unless I did a side by side comparison it would be hard to tell.

My car pulls up smartly from 70+ mph and I have full confidence in them.

[corellian corvette]

Thank you all for the advice. Sorry I didn't respond - actually spend the weekend going over the car and working on a variety of small-ish things that needed to be done.

 

Regarding the brakes - so I made a couple changes that helped. I correctly adjusted the rear drums: I assumed a classic US car which was light drag, but I found the procedure on the forum (tightened nut until drums lock, then back 1/4 turn) worked great.

 

Proper bedding also helped. A variety of light and heaving breaking moves on my street did improve feel.

 

This made things better. Light traffic pedal feel is fine, and moderate driving around town is no problem. I am still disappointed in the "panic stop" performance as it still feels like it takes longer than it should and the brakes (front or rear) won't lock up no matter how hard I press the pedal.

 

This leads me to two questions

 

First - is there any adjustment in the brake pedal? I've noticed on other cars that you can adjust the pedal rod to change height and/or leverage. What physically stops the brake pedal? I want to make sure I'm getting the full range of pedal movement.

 

Second - researching Servo installations is tough. I have a 1982 LHD car with the vertical (square) Master. I only see servos that point forward, or are listed as "single line" systems. How do I install a Servo in my car if I wanted to?

 

Thanks!

[Dan]

If the pedal isn't touching the top of the hole in the cross member where it connects to the rod when it's fully depressed the you are getting full stroke out of it. There are no other stops.

[sonikk4]

To me it still sounds like the pads are not bedded in correctly. I drove my clubman yesterday and had one of those moments on a dual carriageway. The car pulled up very sharply without locking the wheels and nice and straight as well.

I can also lock the front wheels if I push hard enough although I should not need to. The rears I have never locked up but I'm sure if I used the hand brake to affect a hand brake turn I'm sure they will. The fronts do the majority of the work anyway.

The mini brake system is basic compared to modern cars ( mine is single line by the way) and you do need to take this into consideration. I did spend sometime ensuring after the fit all was good with regards to bleeding and of course bedding in the pads.

Even on the MOT the tester said the front brakes were good for being unassisted but even with the rear brakes correctly adjusted etc the braking effect was marginal. This he said was in part due to the lack of weight over the rear of the car.

[Cooperman]

I have never liked the 7.5" brakes with no servo fitted. I have tried without a servo but in the wet I felt that it was difficult to get the point of 'locking up' defined. In fact on test I nearly spun the car into a downhill right hander on slippy tarmac. So I refitted the servo and was happy again.

It's personal choice and many don't like the servo on 7.5" brakes. The Innocenti seems fine with the servo only working on the fronts.

[KernowCooper]

Mine is done on a dual split from rear just like the Innocenti and works just fine, you get lots of bite for those O Sheet moments, and I didn't like the amount of pedal pressure required without the servo or bending the floor. With the servo its different in day and night. The original Cooper 7.5s had the servo, so works for me

[OntarioMini79]

Hi! I am going through a similar situation. I just purchased a 79 Mini 1000. The car came with front discs and its a split system. And a vertical master cylinder. There are no proportioning vales anywhere that I could find. Including under neath the back of the car. The discs and pads have been well used but in good condition other than some rust. After a few test drives the rust scrubbed away. I assumed the brakes were were 7.5's but after measuring the disks they were only 7.0 inches. Brake feel was terrible and stopping power was not good either. I bled the brakes front and back. Nothing improved. I adjusted the back brakes and pedal feel improved dramatically. Stopping power improved but not to the point that i could lock up the fronts or the backs. Unfortunately In my last test run I really got on the brakes to see what would happen and I popped a caliper. The result was a pin hole in the casting that squirted brake fluid out on the disk. 

So now I am in the position do I simply try and find another caliper? Are 7.0 and 7.5 brake calipers different? Or should I do a complete swap with a 7.5 kit that includes everything (plus i get new bearings and ball joints)? And if i do that swap will the brakes feel better but I won't be able to lock them up?

One more question. Will a proportioning valve solve the front/rear bias or were they only used on the single circuit cars? 

 

Lots of questions I admit but I appreciate your opinion.

 

S

[dklawson]

7" disks were Cooper parts, 7.5" Cooper-S.  The 7" disks were said to be an improvement over front drums but most accounts say they were not much of an improvement.  

 

You popped a hole through the caliper?  I think an autopsy is needed.  Look to see what that hole is from as it really should NEVER have happened.  I anticipate you will end up replacing the brakes and related components.

 

What size rims does your car have?  If you have 12" rims you may want to consider doing a brake swap for the larger, late model 8.4" disks and calipers.  Those disks will not fit under 10" rims used on early cars like mine.

[OntarioMini79]

Hi Doug,

 

Yes popped a hole right threw the caliper. In the underside channel just above the disk. Its definitely in the casting.

Thank you for the feed back on disk sizes. I run 10 inch tires.

S

[Earwax]

the pads on the 7 inch disc brakes are smaller than the 7.5s. - by a margin.... that probably accounts for the better stopping power that the 7.5s seem to give.  Unless running concourse or as close to actual replica as possible, the 7.5s are an upgrade worth doing and you can keep your 10 inch rims...IMO  The 7.5 also still have quite a good range of quality brake pad types and brands readily available, possibly more choice than the early 7 inch pads 

[fwdracer]

4-pots on 7.5 discs are a bigger step improvement again if originality isn't your thing. The Minispares calipers run Metro pads, bigger pad area again and choice of suitable pad compounds. They go under (most) 10" wheels.

[jaydee]

Regarding the 7.5 discs:

Theres usually more than one culprit if a bleeded system with good firm pedal still fails at doing its job.

Apart from the fact the autos never gave me a good brake feel.

First you have a problem with the pedal travel-effort, there are different pedals for drum and disc brakes for a reason.

EBC green stuff are really good for a road car, but  what cylinders you fitted at the back?

I would reccomend the use of 5/8 brake cylinders at the back if using 7,5 disc brakes.

Edited by jaydee, 03 October 2014 - 02:12 PM.

[OntarioMini79]

Excellent recommendation. I will check what I have on the rears!

S