Brake pads and brake bias effect

[darock]

Hello and Happy new Year ;)

The question came up after reading through all the threads the search function provided me.
I posted the question on the other thread but it was off topic and probably was not recognized.
It has been discussed already but I could not find any real solution on how to work around the bias effect with aftermarket pads.

My current "brake situation"
My car is a 92 with stock brakes all around. It starts to vibrate when getting hot so at least one of the discs has excessive pad material on it or lets say its "warped" as its the wrong but common term for it. From looking at the discs it may be the left rear because the friction surface does not look as clean as the other three.

I managed to clean up a "warped" disc on my civic with the aggressive break in coating of yellowstuff pads so I thought I might try that with the nsx as well BUT ...

after reading all the threads about brake bias I am a little concerned ...

I don't want to mess up the brake balance by putting yellows all around. So what is the best solution? What pads should be combined to optimize the braking AND get rid of the pad material making the disc "warped"?

Upgrading to the later brake system is a big cost factor so I try to avoid it for now until I find a cheap set to upgrade.

The only thing beside the vibration that really annoys me about the brakes is the ABS because it needs an overhaul. I think it has partially stuck valves as the car tends to lock up wheels but not all the time which sometimes results in a strange sidestep under hard braking. I have the rebuild kit from warren (prime) already but need to find the time to do it.

Long story short ... The more I read the more I am confused :D

The car is a weekend driver. I use it for spirited driving and may go to the track just or fun, not competitive. I have good experiences with Yellowstuff, that's why I prefer those. How do they compare to Dixcel ES or Z's?

All though RedStuff pads are often mentioned here, I had bad experience with them like bad cold performance and squeeling. So before I go RedStuff I would try something new like the Dixcel but that's only my personal experience which may have been influenced by other factors.

Thanks in advance ;)

Bernhard

[NSXGB]

Hi Bernhard.

My advice would be to get the discs skimmed or replaced. Trying to effectively skim them using the coating of the yellow stuff pads may work or may partly work so is not guaranteed.

If you change to the same pads all round you are not going to mess up the brake balance.

I recently had the same dilemma - use an aggressive track pad to remove deposits or skim - I got my discs skimmed on the car which worked well and I'm enjoying the braking again.

I have run the red stuff and OE pads in mine, currently with the red stuff. I get no squeal with them (didn't even fit the anti squeal shims), they seem to work fine from cold and there is no excessive dust. I think there are plenty of UK NSXers running them without problems so would not have a problem recommending them to you.

[Pride]

Hi Bernhard, in my opinion if you know you have disc warp or corrosion issues why not just install complete new discs and pads.
They're not that expensive starting from just £400 complete front and rear from Dixcel.
That way you will probably eliminate your problems in a stroke.
http://www.nsxcb.co.uk/showthread.php?12441-DIXCEL-Brake-Packages-at-amazing-prices/page2
Good luck mate.

[darock]

Thanks guys for the opinions. Swapping all discs/pads is probably the best way ...

So what is all the discussion about the brake bias about then if that does not effect it?

The idea behind the yellowstuff "skimming" my "warped" disc was to stay cost effective to save money for the future bigger brake upgrade.

I know myself and replacing discs and pads will result in a big €€€ investment because I can't just buy basic parts, it must at least be one step better. :D

What makes the plain Dixcel discs worth twice the money of Mintex?

How do the similar priced Supertech slotted rotors compare to the Dixcel slotted?

Bernhard

[NSXGB]

I paid £80 to have my discs skimmed on the car, that's a cost effective option...

Sounds like your money would be better spent on your current ABS system?

[darock]

Sadly there is not a single shop that can skim the discs on the car. As discs are so cheap nowadays, nobody knows how to do that any more :(. There are no real mechanics left in Austria. The only thing they can do is plug in the OBD computer and hope that it will tell them what to do step by step to fix the problem. They can't even change brake pads without messing up totally. Honda filled the wrong oil in my mum's Hybrid Jazz because they are so dumb, they can't even read the manual. Seriously I wouldn't give them the key to my NSX even if they pay me ...

I agree on the ABS topic. I will rebuild it and I hope it will work like intended afterwards. There are a lot of positive experiences with that on prime. If that does not work out I can still go the NA2 ABS route but that's a nearly 1700€ invest. The "rebuild kit" by warren@prime was $60 so absolutely worth a try.

Bernhard

[NSXGB]

...sounds like my last main dealer experience...

If you can justify it, the 2000+ ABS upgrade is the way to go. One of my favourite upgrades.

[darock]

If you can justify it, the 2000+ ABS upgrade is the way to go. One of my favourite upgrades.

Can you tell me what the difference is? I mean, I know the mechanical differences but what is the actual difference you can feel as a driver?

Bernhard

[NSXGB]

Can you tell me what the difference is? I mean, I know the mechanical differences but what is the actual difference you can feel as a driver?

Bernhard

Firstly, you will never hear that dreadful chirping noise ever again!!
Secondly its a much more up-to-date system with more processing power which reacts faster. You feel a massively quicker response in pedal kick back.
Nice, neat unit with bonus weight savings.

[darock]

That chirping noise is really dreadful :D

I don't think those pumps sounded so badly when they were new ...

Bernhard

[nobby]

Abs upgrade is a must IMHO

[darock]

Yes, its on my todo list but for now I have to live with what I have and make the best of it.

So I will probably put in some new discs and pads.

I still don't know what makes the Dixcel discs more than twice as pricy as Mintex or Nipparts all though they are all basic plain discs. Nothing high-tech ...

Bernhard

[Pride]

Hi again Darock, if cost is an issue then go for the cheapest brand option because it will still be a big improvement against your worn discs at the moment.
And as you are saving for a big brake upgrade at a later date anyway why spend more than you need to??
At the end of the day to be honest it is a small diminishing return on the more you spend especially at entry route level.
You can then drive with smooth brake pedal feel.:)

[Mistercorn]

If there is something that is significantly better about what appear to be very similar disks it would be great to know. I'm happy to pay extra for better quality if required, but not just for a name on a box.

MC

[Pride]

If there is something that is significantly better about what appear to be very similar disks it would be great to know. I'm happy to pay extra for better quality if required, but not just for a name on a box.

MC
As you no doubt know MC, buying a better brand name, particularly on products like entry level brake discs, are very debatable as to why one costs more than the other.
The one thing you do get though is better self confidence in buying a better brand name which is all down to how the brand markets itself and what you believe when you read their blurb.:rolleyes:

[Mistercorn]

To me it could be higher quality raw materials, tighter tolerances, different manufacturing techniques/processes. All of these could be valid reasons why a seemingly identical part is twice the price. Or it could just be trying to make more profit. Either way as a consumer it is good to know.

MC

[Pride]

There you go then, you answered your own question after all.
Power of the blurb!!

[darock]

As a customer you definitely need a good blurb radar. :D

[darock]

I measured the discs today.

The front discs are at around 27mm
The rear discs are at just below 21mm

So the discs are like new. Pads front are like new, rears about 2/3 left.

Is a "warped" disc in the back feelable in the steering? I think only the front ones are noticeable in the steering.

I tend to leave the rear discs alone as they are like new and just replace the front ones. New pads all around for sure.

The right front discs looks like it may has some pad material on it.

Thinking about going the cheapest route in terms of brake parts but invest in the newer abs as mine seems its really tired after I removed it from the car. Opened another thread about that.

Bernhard

[Pride]

To confirm excessive disc warpage you will need to use a dial gauge as just a minimal amount can cause all sorts of feed back issues.
If you don't have one of these gauges or don't know how to use one then an old favourite trick of mine is to just clamp off both the rear flexible brake pipe hoses just before the callipers and go for a short test drive.
In this way you will instantly know if the fronts are ok and how bad the rears are.
You can buy these very easily and inexpensively on eBay.
http://www.ebay.co.uk/itm/Taskmaster-Brake-Pipe-Clamp-Tool-Steel-Bar-Type-Suitable-for-Brake-and-fuel-hose-/351257930168?pt=LH_DefaultDomain_3&hash=item51c89aa9b8
Good luck.

[darock]

I actually have a dial gauge and also know how to use it :D

I also like the idea of the clamp but as I have the ABS out of the car right now, there is no way I could go for a test drive :(

Bernhard

[Pride]

I actually have a dial gauge and also know how to use it :D

I also like the idea of the clamp but as I have the ABS out of the car right now, there is no way I could go for a test drive :(

Bernhard

Oh!! in that case who needs the ABS unit anyway, just rely on good old fashion cadence braking, and it will save you both time and a fortune on repairing or replacing the old one, just think Bernard, guaranteed NO more chirping noises but just be careful when driving round those icy Viennese mountains.:):)

[Kaz-kzukNA1]

Ah.... From what I read so far, you are talking about the brake disc judder and life-ing in the order of 1mm or 0.1mm the best.
In fact, it's not that simple and you need to be in the order of 0.001mm measurement and that doesn't even take any consideration regarding the temperature or molecule level discussion.......

Some questions for you....

When was the last time you had your brake caliper overhauled?
Can you feel the judder at the steering wheel through your finger as well as at your back? Or, is it just one side (steering or through the back)?
When did you start experiencing this judder? Immediately after you bought your NSX or after you owned it for a while?

How do you cool down the brake as well as bring the temperature up during the weekend spirited driving and also during track day?
How do you drive on the way to the track?
Do you use parking brake during track day event?

By the way, with the classic ABS, even if it is in perfect working order, you may end up locking the wheels on low mu (u) surface. Already tested many times and experienced the scary moment by myself.
Hence, upgraded the ABS to the latest spec.
Having said this, I don't feel comfortable driving on the public road without ABS even with the classic spec apart from when on track.
With the Classic ABS, I just pull the parking brake 1 click for 30sec and disable it while driving in the pit lane.

Kaz

[darock]

Some questions for you....

When was the last time you had your brake caliper overhauled?
Can you feel the judder at the steering wheel through your finger as well as at your back? Or, is it just one side (steering or through the back)?
When did you start experiencing this judder? Immediately after you bought your NSX or after you owned it for a while?

How do you cool down the brake as well as bring the temperature up during the weekend spirited driving and also during track day?
How do you drive on the way to the track?
Do you use parking brake during track day event?

Kaz

Hey Kaz,

I don't think the calipers have been overhauled ever. I greased the floating pins of the left rear caliper recently because they felt sticky. A lot of old grease in there. Works ok now. I should probably check that on all of the calipers.

I can feel the judder through the steering but also my passengers can feel it.

I think I had it the first time I drove the car sporty so is must have been there already when I bought the car. Didn't feel it during the test drive before I bought it but also did not drive it hard in city traffic.

I avoid braking to a full stop with hot brakes. Always get off the brakes and let the car roll to a full stop unless its really an emergency braking. When I drive any of my cars harder I give it some km to cool down. Regarding warming up, I don't know. I have never thought about warming up a brake. As I drive my cars really careful during warmup until the engine oil is up to operation temperature I probably also warm up the brake a little by just using it normal.

I can't say anything about track day because I haven't been to one with the NSX. However, I never use the parking brake. I always park the car in gear unless its downhill.

One thing to add that might be interesting for you. I have read all your blog entries and compared to the corrosion on the pictures you post there, my car looks like new. That bracket holding the ABS connectors looks totally new on my car. Also brakes and suspension. No heavy corrosion whatsover. My car was maintained really well by its first and second owner with full service history at Honda Dealerships. Only the previous (third) owner was a jerk but he did not have the car long enough to really harm the car.

[Kaz-kzukNA1]

Seems like you found one of the cause of the judder by yourself.
If you don't know when was the last time your brake caliper was overhauled and if you only drive your NSX occasionally, then chances are, your pistons are not moving smoothly.
One of the most well known cause for the brake judder that happens over long period/distance (months/years, a few thousands miles) on cars not driven regularly.

Not sure what kind of brake pad you use but does it ever squeak?
Do you see rust on the disc the next time you decide to drive your NSX?

Replacing the brake pad and disc may fix the judder short term but eventually, the issue may come back over many months/miles with your brake caliper condition.

As mentioned in my previous post, you only need in the order of 0.001mm for the disc surface condition to cause the judder and this measurement is in cold static condition.
If you want to learn more, there are lots of good patent documents available on the brake system of the Bullet Train. By the way, if you can generate enough heat and look into molecule level, you can warp the disc.

Short term rust is not big enough factor to be considered as part of judder mechanism but if it was left for months, it does.
Ideally, you want the disc to rust evenly but in real world, unfortunately, that will never happen.


So, if you have question mark on your brake system, my recommendation is to check the piston movement as well as the slider pin condition.

Can you push/rotate the piston without excessive force?
For the front, you should be able to do so with just your finger.
For the rear, you will need some sort of tool to rotate the piston but again, should move smoothly with just your finger.
Make sure to set the ' + ' recess against the inner pad notch/pin before placing the caliper back in place.

I believe you are changing the brake fluid at least every 2 years but have you checked the piston movement after you started owning your NSX?


If in doubt, overhaul the caliper/bracket and decide what to do with the master cyl.
Then, depending on the budget, replace all four disc and pad at the same time or replace just the front or rear disc/pad as a set at a time but ideally, all four disc/pad together.


If you are staying with the early spec smaller caliper/disc size, forget about the EBC, Dixcel, etc for the rear disc.
Just visit your local Honda garage and ask for the price of OEM one.
You should be able to find it at very reasonable price. The last time I bought them for another owner, I think I paid less than GBP50 each including VAT. Cheaper than the EBC.
It could be out of stock but worth checking.


Kaz

[darock]

So what I will do next is get the calipers off and try to move the pistons and floating pins. I can actually take the calipers off and home as the brake system is opened anyway. Its too cold in my garage to do much work on the car.

Obviously I don't know how the calipers look inside but from the outside they are reasonably clean without rust. Given the car has 235tkm done so far, they look impressively clean.

I have not changed the brake fluid (only have the car for 5 month) as it looks clean like new but will have to do the change anyway as I removed the ABS. I believe it has been changed regularly. Even the clutch hydraulics fluid looks clean which is something you don't see often on a Honda as you probably know.

Last time I was in my garage to remove the ABS I noticed a little bit of rust on the front discs but nothing to worry about. Normally I did not see any rust on the disc. The car is parked in a dry but unheated garage so condensation might happen if temperature drops rapidly.
All brake parts seem to be OEM Honda Parts. I remember that the car sometimes had a little brake squeak when starting a trip. That might indicate your suggested sticking part of a caliper.

There is no way I get brake discs for 60 Euros here in Austria. The prices at our honda dealers are mostly a complete rip off. I just paid 8 Euros for one suspension bolt of my sisters Insight that costs $3 in the US. Sadly I needed it now.

So .. next step is removing the calipers and investigate.

Bernhard

[NSXGB]

Darock, I think you should check out the For Sale section: http://www.nsxcb.co.uk/showthread.php?12638-FS-ABS-Conversion-kit-for-LHD-COMPLETE

[darock]

You got PM ;)

Today I asked the Honda dealer how much a brake disc is and he replied 550 euros! I thought thats a joke but it isn't. Thanks to Honda Austria for ripping off customers ...

bernhard

[Hagasan]

You got PM ;)

Today I asked the Honda dealer how much a brake disc is and he replied 550 euros! I thought thats a joke but it isn't. Thanks to Honda Austria for ripping off customers ...

bernhard

I've got two brand new Genuine front discs in the box but I'm sure the shipping from the UK will make it too expensive?

[Kaz-kzukNA1]

You got PM ;)

Today I asked the Honda dealer how much a brake disc is and he replied 550 euros! I thought thats a joke but it isn't. Thanks to Honda Austria for ripping off customers ...

bernhard
Probably you asked about the Front disc (45251-SL0-030) and not the Rear one (43251-SL0-010).
For the Front, Euro550 is not surprising when looking at the HUK price and that's for just one single disc. You need two of them for the front set.

You can get fairly good idea on the parts cost through Lings Honda website; http://www.lingshondaparts.com/
Once you got to the desired parts section, just remove the '_pfk' just before '.php?' in the middle of the address bar and you will get the proper Honda parts code rather than the Lings own parts no. starting like PFK****.


As in my post, the rear disc at the moment is GBP46.19 inc. VAT EACH (you need two discs for the front set) from HUK and as I don't know the local tax in Austria, not sure of the final cost but should not that far off.


For the Front, just get EBC PD (Plain Disc) or equivalent. No need for the slotted or drilled for the street usage.
If you visit www.ebcbrakeshop.co.uk (http://www.ebcbrakeshop.co.uk/) and look for D627 (this is for the early model smaller disc dia. 282mm), it is currently sold at GBP130.05 inc. VAT, inc. next day delivery within UK as a front SET (this is sold as 2 discs as 1 set at this price, unlike the OEM one sold one disc each separately) so please check the actual cost delivered to your country or I'm quite sure you have lots of vendors dealing with EBC, Brembo, etc in your country offering good deal. Just make sure to buy it from reliable source. It's the brake system.


Kaz

[darock]

@Hagasan
Thanks for the offer. I will get the Nipparts discs for 70 euros all inclusive. Should do the job until I find a good set of brakes to do the bigger brake upgrade.

@Kaz
I definitely asked for the rear discs. I even asked twice to confirm after I heard the price. I thought he was kidding me.

EBC Austria main dealer is actually only 10 min away from me. Have made business with them already.

But I think I might try the Dixcel ES Pads. Just because I want to try something new :)

Bernhard

[Pride]

Darock, sorry mate but I have to mention this, you seem to ask loads and loads of questions for opinions and answers about your brakes and then go your own route in the end anyway!! :(

[darock]

You are absolutely right mate, I read all the opinions and then find a way to do it. I happen to be a real enthusiast but on a tight budget. Sorry if it seems I won't follow any advice. I collect all the information and try to make it work with my budget as good as possible with still keeping future upgrades in mind. Not that easy sometimes. I love this forum with all the information.

Big big thank you to all of you giving me their opinion and advice :)

cheers,
Bernhard

[Kaz-kzukNA1]

Sometimes, I feel what's the point in writing all these posts.....

Good luck with your own way.


Kaz

[darock]

Sometimes, I feel what's the point in writing all these posts.....

Good luck with your own way.


Kaz

you and your posts are are a big part of the reason why I do all that. Especially your blog and the pictures encouraged me to start the projects. that also has the biggest influence on how I aproach the tasks and try solving issues.

Your input on the calipers will save me a lot of time when I take them off for investigation.

So "my" way as I called it is probably the wrong term.

if you ever come to Vienna, give me a call. Talking live and maybe with a beer always is different than using the forum where personal interpretation plays a big role. As English is not my first language I probably also mess it up to write the posts perfectly polite and fail to express what I mean. Sorry :/

Bernhard

[darock]

Good morning

Thank your for your email but we regret that we are unable to supply this component as it is no longer available or order from the manufacturer.

that's the response from lingshonda regarding availability of the rear discs :(

Bernhard

[NSXGB]

Another option for you is to buy the brackets to space your calipers out so you can run the 1997+ size discs (from EBC maybe), and your new ABS....
I think Adnan at AS Motorsport sells the brackets which aren't too expensive.

[darock]

Another option for you is to buy the brackets to space your calipers out so you can run the 1997+ size discs (from EBC maybe), and your new ABS....
I think Adnan at AS Motorsport sells the brackets which aren't too expensive.

I found a thread on prime where Adnan advertises the brackets. I will send him an email to check the price.

From what I read here, especially Kaz's posts about brake bias, changing just the brackets for the bigger discs will most likely screw up the brake balance. I have actually been in an emergency brake situation where I could easily lock up the front tires.

My dream setup would be the bigger brake from 02+ model while keeping the bigger piston old caliper in the front and the NSX-R abs. But that all together does not fit my budget right now :(

Bernhard

[Silver Surfer]

Just get stickier front tyres to stop you locking the front.... Just a thought.

SS

[Pride]

Just get stickier front tyres to stop you locking the front.... Just a thought.

SS

I use these, Toyo R888, simply put, phenomenal.

http://data.motor-talk.de/data/galleries/0/139/2110/33900855/toyo-20semi-20slick-20reifen-profil-7782338485276006989.jpg

[darock]

Just get stickier front tyres to stop you locking the front.... Just a thought.

SS

That is exactly what I did :)

I swapped the ugly heavy bling bling 18/19" rims with Nankang tires the DPO put on the car for a set of Advan T7 17/18" with Federal 595RSRs. Wanted to give the Federal tires a try as they have good reviews everywhere. I can't say anything bad after driving them about 500km. Great all around performance.

I have run the R888 on our auto slalom car and in wet condition they have not been that good. In dry condition a different league though.

Bernhard