First (and last) time Toyota Owners ...

[Bper]

17 minutes ago, Mojo1010 said:

Ceramic brakes and discs cost a lot of cash, €10000 a set I've read. No brake drums for me, brake discs perform 

 How about if ceramic discs and pads were fitted as standard on new cars would you welcome it or still prefer the norm?👍

[Bper]

2 minutes ago, Bper said:

 How about if ceramic discs and pads were fitted as standard on new cars would you welcome it or still prefer the norm?👍

Sorry meant to say if they could be designed for normal cars.

[Mojo1010]

6 minutes ago, Bper said:

 How about if ceramic discs and pads were fitted as standard on new cars would you welcome it or still prefer the norm?👍

Not when it can cost a few thousand pounds more. Then when it's time to change....... Don't think it will ever be standard because of cost. 

[anchorman]

6 hours ago, Bper said:

Hi Don,

Thanks for the very informative post on brakes, I am sure this will help many members to understand how brakes are designed and how they wear.

Just a couple of questions, for drivers that only do low mileage are they better taking the car for a run and applying the breaks a bit later to increase the friction and heat to prevent issues with wear. Also are ceramic breaks whilst more expensive a better option for low usage.👍

I don’t know how to answer that to be honest Bob.  Like I said, for most people there isn’t a problem so for those that do very low mileage is the prospect of going out heating their brakes up going to be less troublesome and costly than fitting pads and discs every 4 years?  I accept that our absent friend who started all this has been quoted £600.  I realise it isn’t the same for everyone but I can fit pads and discs in my sleep and I’d only pay a quarter of that for parts.  He would do better independently but Toyota will be very competitive if pushed.  If he’s wound them up he might not get far.

1 hour ago, Bper said:

Hi Iain, on a daily basis we see so many cars parked that are used very infrequently as they never seem to leave the same position. So that being the case does this mean that the brakes on these cars will suffer from quicker deterioration and higher costs due to lack of use.However a number of neighbours leave cars for weeks before driving and then only some of them only do very short journeys etc.

I wonder if lack of car use and brake wear is something many people are aware of.

 

Yes, providing the conditions are the same, there is nothing different between Toyota and every other “normal car” brand.  By conditions I mean same exposure and environmental conditions.  I had a mate who bought a lovely looking RAV4 but it had lived by the sea and was rotten as a pear underneath. I bought one from Saltburn once and it was a couple of miles from the sea but I could taste salt in the air.  I didn’t keep it long so no harm to me but it might well affect it in years to come.

1 hour ago, Cyker said:

It depends what you mean by ceramic brakes, but often these fancier brakes are meant for track use where they can operate at high temperatures without loss of performance.

Standard automotive brakes are actually the best kind of brake for normal use - The standard iron disc and organic pad have better 'bite' from cold than higher performance brakes.

Things like carbon-ceramics are good for track use as they have high fade resistance, but feel worse than normal brakes when stone cold. In anything with regen braking, they'd always be outside their operating temperature. They also cost more than what I paid for any of my previous cars  

You can get sintered ceramic pads that work with normal discs - The factory pad for the jappy-made Mk1 Yaris used Akebono ceramic pads which were really nice as they produced no visible dust and were always quiet, unlike whatever my Mk4 came with which is like nails on a chalkboard in summer when they've gotten hot! Not sure why Toyota moved away from them; May just be a Euro-thing as I think Toyota are forced to use a certain amount of local components and I don't think anyone makes road-use ceramic pads in Euro-land like Akebono does for japan. (Which is also why the jappy and french Mk1s had completely different brake systems! That was such a pain in the proverbial the first time I needed to get new pads for my old Mk1 D4D...! IIRC there were something like 8 different combinations!)

 

Exactly Cykes, there are disadvantages with carbon fibre, ceramic and kevlar based pads in that apart from being hellish expensive, they are made for a purpose and they might be good for 1000C on a track but lack feel and refinement pottering around town.  I once got approached by one of the regional police forces for some “better” pads.  It turned out that we already made them, they were ordinary pads baked twice which cures the resin (you complete the cure on standard pads by driving them).  They thought the sun shone out of my backside after trying some and thats all they’ll use now.

[anchorman]

1 hour ago, Bper said:

Sorry meant to say if they could be designed for normal cars.

It makes me smile when people buy “coloured pads” and grooved discs etc thinking they’ve got something special.  The true completion pads might have less steel in them but they’ll still stick and play up with low use.  They are good for competitions but not everyday road use.

[TonyHSD]

Here for the drum brakes 👍

 

[Yugguy1970]

If the OP doesn't like Toyota any more, it's his money and his choice.

It's spawned a fascinating thread about car brake technology.

I remember decades ago, in the 80s, our school coach had a "Tesla" braking system.  Some kind of electromagnetic system.  

Makes me wonder, have braking systems really developed much?  It's still basically jamming two things together and relying on friction.

[bathtub tom]

1 hour ago, Yugguy1970 said:

I remember decades ago, in the 80s, our school coach had a "Tesla" braking system.  Some kind of electromagnetic system. 

Eddy current retarder (https://en.wikipedia.org/wiki/Eddy_current_brake) produced by spinning magnets close to a metallic disc. The same system they used for speedometers (nearly said speedos) from before I was born (1940's).

[anchorman]

1 hour ago, Yugguy1970 said:

If the OP doesn't like Toyota any more, it's his money and his choice.

It's spawned a fascinating thread about car brake technology.

I remember decades ago, in the 80s, our school coach had a "Tesla" braking system.  Some kind of electromagnetic system.  

Makes me wonder, have braking systems really developed much?  It's still basically jamming two things together and relying on friction.

To my knowledge there’s nothing yet to replace the “foundation” friction brakes but several regenerative brakes (like Tesla which is similar to our Yaris) and then there are dynamic brakes that do a similar thing that reverses the field in traction motors but the heat generated is wasted to atmosphere.  There are also hydrodynamic brakes which use gearbox pumps or turbines to slow vehicles.  These pump fluid against a fixed member and the back pressure slows the transmission.  They also get very hot.  Legislation dictates that there must be a fail safe method and that must meet strict requirements with or without auxiliary brakes.  That means whatever auxiliary brake is used, you must retain the foundation brakes in all cases. Trucks can have exhaust brakes which block the exhaust and the back pressure slows the engine and there are engine brakes that open the cylinder valves to cause suction on the downward stroke.  There are maglev trains that use magnetic fields to propel and stop but I’ve not heard of those being applied to vehicles.  Of course a drogue chute would look cool on a Yaris but not seen one of those either 😉

[Max_Headroom]

14 hours ago, anchorman said:

Trucks can have exhaust brakes which block the exhaust and the back pressure slows the engine

Mine has this and it works a treat the negative is the system may be a bit bulky for a car.

[Cyker]

As much as I love the idea of air brake panels to popping out of my car like KITT in Super Pursuit mode, I don't think it would be permitted on modern cars

I suppose I could pull the fuel-filler flap lever but it's not quite the same...

 

 

 

 

 

[TonyHSD]

4 hours ago, Cyker said:

As much as I love the idea of air brake panels to popping out of my car like KITT in Super Pursuit mode, I don't think it would be permitted on modern cars

I suppose I could pull the fuel-filler flap lever but it's not quite the same...

 

 

 

 

 

You gave me a good idea, me and my mates to open together all doors at 40mph and see what happens. 😂👌

[Bernard Foy]

5 hours ago, Cyker said:

As much as I love the idea of air brake panels to popping out of my car like KITT in Super Pursuit mode, I don't think it would be permitted on modern cars

I suppose I could pull the fuel-filler flap lever but it's not quite the same...

 

 

 

 

 

And there was I thinking that the reason I bought the Yaris was so I wouldn’t have to pull the fuel filler lever as often as before, but now I have to use it as a brake assist 😤🤣😂🤪

[bathtub tom]

23 hours ago, anchorman said:

Trucks can have exhaust brakes which block the exhaust and the back pressure slows the engine and there are engine brakes that open the cylinder valves to cause suction on the downward stroke.

I don't see how blocking the exhaust would act as a brake. There are 'jake brakes', which open an additional valve in the cylinder head and use pumping losses to !Removed! the vehicle. Noisy damn things and banned from using them in some Australian towns I believe.

[Eddiefh]

Tony must have problem with internet provider that or he’s been abducted 

[anchorman]

24 minutes ago, bathtub tom said:

I don't see how blocking the exhaust would act as a brake. There are 'jake brakes', which open an additional valve in the cylinder head and use pumping losses to !Removed! the vehicle. Noisy damn things and banned from using them in some Australian towns I believe.

It’s called an exhaust brake.  Very common;

 

https://en.wikipedia.org/wiki/Exhaust_brake

[anchorman]

16 minutes ago, Eddiefh said:

Tony must have problem with internet provider that or he’s been abducted 

I think he’s out picking the back doors up off his Auris.

[Cyker]

44 minutes ago, bathtub tom said:

I don't see how blocking the exhaust would act as a brake. There are 'jake brakes', which open an additional valve in the cylinder head and use pumping losses to !Removed! the vehicle. Noisy damn things and banned from using them in some Australian towns I believe.

It's similar to reason why the cat, DPF and stalled turbos cause performance loss - The exhaust doesn't just leave the car on its own, it's pushed out by the cylinder moving up and pushing it out past the open exhaust valves.

By having any sort of obstruction in there, e.g. cat, DPF, turbo vanes, or in this case the exhaust brake butterfly valve, the rising cylinder will encounter much more resistance trying to push the exhaust gasses out, which saps power surprisingly quickly.

It's pretty much the other end of the same problem on the intake side, where the throttle restricts air intake which saps energy from the engine, and why Toyota and other manufacturers invented things like the Valvematic system, which lets the car run wide open throttle and use the intake valve timing to control the amount of air going in, instead of making the engine fight against a partial vacuum caused by a conventional throttle.

That does help the car slow down tho' and is the source of the majority of the normal 'engine braking' force in petrol engines.

[Cyker]

53 minutes ago, anchorman said:

I think he’s out picking the back doors up off his Auris.

Do we need a disclaimer? Something like "We at TOC do not advise or endorse using a vehicle's doors as ad-hoc air brakes and do not take any responsibility for any consequences resulting from the unsanctioned use of them as such."  

 

[Max_Headroom]

 

Quote

Trucks can have exhaust brakes which block the exhaust and the back pressure slows the engine 

 

Exhaust brake flap test. 

 

 

[Trewithy]

Some of the posts above remind me of the old joke about the man who drives off a cliff.  As he flies through the air he says to his passenger "don't worry, I've got air brakes....and wing mirrors".