Mechanical Sympathy.Thing of the past.

Mechanical Sympathy.Thing of the past.

Author
Discussion

jamei303

2,996 posts

155 months

Tuesday 21st August 2018
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I like to drive in heavy rain without using my wipers, also I keep the lights off as much as possible because I have great sympathy for the filaments.

TooMany2cvs

29,008 posts

125 months

Tuesday 21st August 2018
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Mave said:
66mpg said:
Another point to consider: since the demise of brake pads with asbestos the friction material wears the disks much faster. We’re all going to be buying more disks than we used to.
It's probably been 20 years since they stopped putting asbestos into brake pads so I think we should be used to it by now! :-)
Longer than that - "Asbestos Free" was being shouted about in the mid-late 80s, and it's 20 years next year since they were completely and utterly banned (but that was irrelevant, since they'd long-since disappeared anyway).

droopsnoot

11,810 posts

241 months

Tuesday 21st August 2018
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On a slightly different slant, I was at Tatton Park at the weekend where, every so often, someone in the "Dream Cars" tent would start an almost-new Lamborghini of some kind and, a few seconds later, rev it repeatedly until it was bouncing off the rev limiter.

Should I have made a note of the VIN and make sure I never buy it, or do modern engines cope with that kind of stuff now?

xjay1337

15,966 posts

117 months

Tuesday 21st August 2018
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colonel c said:
Looking at my recent service invoice for my Defender. I see an advice note stating ‘rear brake discs required next pad change’.
Nothing unusual there. However it got me thinking. In forty odd years of motoring I have never had to replace disks before. Very rarely pads and never a clutch. I like to think this is down to some extent of driving with a scene of mechanical Sympathy. Is this another part of driving that will fall by the wayside as EVs and sophisticated hybrids takeover from the conventional internal combustion engine and mechanical power train?
My M135i needed new rear pads at 32k.
Road car not tracked or abused.

The discs were OK but ideally would be changed.

Back in the day brakes were rubbish and didn't work so of course nowadays they are used more... people generally go faster.

I find most people to be generally mechanically sympathetic in that they tend not to rag their cars.

RobM77

35,349 posts

233 months

Tuesday 21st August 2018
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Reg Local said:
RobM77 said:
It's something I often think of and I'm not sure if it's strictly mechanical sympathy or not... Like I suspect you do, if I'm doing 50mph in a 50 limit and see a 30 limit coming up, I try to judge where I can back off so that I'm doing 30mph when I enter that limit without braking. Likewise, if there's a bend coming up I judge the turn-in speed I want in a similar fashion. Same for junctions, traffic lights (cold or hot etc) etc. I've noticed that most people don't do this, and I've often wondered why. Is it all the cycling I do and how that gives me an appreciation of energy and momentum? Or is it mechanical sympathy? I'm not really sure.

One interesting result of this is that despite driving very quickly, I record pretty high mpg figures. The downside is that when I'm a passenger and people are actively driving their car towards a red light it makes me squirm a bit.

One thing it might be is simply looking and thinking further ahead... Most of the driving problems that certain bad drivers I know have simply boil down to not looking far enough ahead. This also shows on motorways, where I'd hazard I guess you can stick to a speed and flow in and out of lanes appropriately, whereas others seem to be constantly slowing for lorries and then accelerating to pass them - this isn't mechanical sympathy, just thinking ahead.
Completely agree.

I’ve been driving for 32 years & well in excess of a million miles & I’ve never had to replace a clutch. I’ve had my current car from almost new - it’s close to 40,000 miles now on it’s first set of brake pads & they’re absolutely nowhere near ready for replacing. And no, I don’t drive it slowly (see my Youtubes!).

A friend has had his car from new & it’s now on 240,000 miles & still on its first clutch.

An anticipatory driving style translates automatically into a mechanically sympathetic driving style (and a more fuel efficient style).

Mrs Local, on the other hand...
Same here - 24 years on road and 17 on track, and that includes several that have been measured and put back in. I think that is genuine mechanical sympathy though - I simply rev match every gearchange and don't ride the clutch. Not braking, as per the topic of this thread, is very much linked with better observation and planning.

survivalist

5,614 posts

189 months

Tuesday 21st August 2018
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IME by far the biggest factor is modern stability control systems. The early ones basically just cut engine power. The more modern clever systems use a lot more braking for stability, especially the rear brakes.

On the plus side, cuts down on tyre wear which may ultimately be cheaper if you’re running 265 section tyres.

But Regardless of rear brakes and stability control, if agree that mechanical sympathy seems to be a thing of the past. In reality I think it’s more of a case of smashing over speed bumps at 40 mph. Never checking oil levels, tyre pressures, tread depth etc

Potentially because the perceived costs of cars have dropped massively (eg for many it’s gone from the second most expensive purchase you make to a monthly cost) , combined with massively more competent cars - the abuse they can take is huge so people have less and less interest in the details of motoring and just hop in and turn the key/press the button etc

Edited by survivalist on Tuesday 21st August 20:17

SidewaysSi

10,742 posts

233 months

Tuesday 21st August 2018
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Reg Local said:
RobM77 said:
It's something I often think of and I'm not sure if it's strictly mechanical sympathy or not... Like I suspect you do, if I'm doing 50mph in a 50 limit and see a 30 limit coming up, I try to judge where I can back off so that I'm doing 30mph when I enter that limit without braking. Likewise, if there's a bend coming up I judge the turn-in speed I want in a similar fashion. Same for junctions, traffic lights (cold or hot etc) etc. I've noticed that most people don't do this, and I've often wondered why. Is it all the cycling I do and how that gives me an appreciation of energy and momentum? Or is it mechanical sympathy? I'm not really sure.

One interesting result of this is that despite driving very quickly, I record pretty high mpg figures. The downside is that when I'm a passenger and people are actively driving their car towards a red light it makes me squirm a bit.

One thing it might be is simply looking and thinking further ahead... Most of the driving problems that certain bad drivers I know have simply boil down to not looking far enough ahead. This also shows on motorways, where I'd hazard I guess you can stick to a speed and flow in and out of lanes appropriately, whereas others seem to be constantly slowing for lorries and then accelerating to pass them - this isn't mechanical sympathy, just thinking ahead.
Completely agree.

I’ve been driving for 32 years & well in excess of a million miles & I’ve never had to replace a clutch. I’ve had my current car from almost new - it’s close to 40,000 miles now on it’s first set of brake pads & they’re absolutely nowhere near ready for replacing. And no, I don’t drive it slowly (see my Youtubes!).

A friend has had his car from new & it’s now on 240,000 miles & still on its first clutch.

An anticipatory driving style translates automatically into a mechanically sympathetic driving style (and a more fuel efficient style).

Mrs Local, on the other hand...
Same here. Unfortunately most people don't much care for driving and are really quite poor at it. I am no driving God but I have found even the average track day goer still lacks mechanical sympathy and smoothness. On a few occassions it made me nervous being a passenger so now I tend not to ride alongside people on the circuit.


kambites

67,461 posts

220 months

Tuesday 21st August 2018
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xjay1337 said:
I find most people to be generally mechanically sympathetic in that they tend not to rag their cars.
I think the massive increase in performance, especially low rev torque, of mainstream cars in recent years is the main trigger for that.

V8RX7

26,765 posts

262 months

Tuesday 21st August 2018
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My mate sold his 7.5ton Merc Recovery truck with IIRC 300,000 miles on it

The buyer asked when it had last had a clutch

He was surprised to find out it had never had one.

He wasn't sure whether to be pleased that it had been treated so well or upset at the thought that a 300k clutch was still fitted.


warch

2,941 posts

153 months

Tuesday 21st August 2018
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Lorry clutches are built to take the strain. Most cars with clutch problems actually have had a dual mass flywheel failure. Incidentally I was warned by a garage that my DMF was about to fail about four years and 50k miles ago, it still hasn't failed and isn't any worse than it was then.

Cars are heavier than they used to be so suspension wears faster, also roads are in a poor state so it exacerbates the problem.


njw1

2,053 posts

110 months

Tuesday 21st August 2018
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Regarding high mileage clutches, it's obviously going to depend on how the car is used, lots of motorway work and theoretically it'll last forever, stop start town driving will wear it out a lot quicker. I had to fit a new clutch to my Mondeo a while back, at nearly 150k the friction plate was barely worn (it still had the little grooves in it), the dmf was checked as per the manufacturers specs and found to be barely worn (so it stayed where it was!) but the slave cylinder had disintegrated. I also had to do the rear discs on the e39 for it's mot earlier in the year, it wouldn't have surprised me if it was the first time it had had rear discs judging by the fun I had getting one of them off!

Edited by njw1 on Tuesday 21st August 20:59

Test driver

348 posts

123 months

Tuesday 21st August 2018
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spookly said:
Driving in a way to conserve brake pads and disks makes Jack a dull boy.
Exactly. Rolling road blocks ffs; shameful.

Jaroon

1,441 posts

159 months

Tuesday 21st August 2018
quotequote all
RobM77 said:
It's something I often think of and I'm not sure if it's strictly mechanical sympathy or not... Like I suspect you do, if I'm doing 50mph in a 50 limit and see a 30 limit coming up, I try to judge where I can back off so that I'm doing 30mph when I enter that limit without braking. Likewise, if there's a bend coming up I judge the turn-in speed I want in a similar fashion. Same for junctions, traffic lights (cold or hot etc) etc. I've noticed that most people don't do this, and I've often wondered why. Is it all the cycling I do and how that gives me an appreciation of energy and momentum? Or is it mechanical sympathy? I'm not really sure.

One interesting result of this is that despite driving very quickly, I record pretty high mpg figures. The downside is that when I'm a passenger and people are actively driving their car towards a red light it makes me squirm a bit.

One thing it might be is simply looking and thinking further ahead... Most of the driving problems that certain bad drivers I know have simply boil down to not looking far enough ahead. This also shows on motorways, where I'd hazard I guess you can stick to a speed and flow in and out of lanes appropriately, whereas others seem to be constantly slowing for lorries and then accelerating to pass them - this isn't mechanical sympathy, just thinking ahead.
I am a train driver, InterCity. This is how we like to drive trains, with anticipation and margin. It is more comfortable, more frugal and safer. This driving style comes under the umbrella terms "defensive driving" or "eco driving." This is also a more engaging way to drive as you can always improve. Mechanical sympathy go hand in hand with passenger comfort and I enjoy it very much. That said I am not mechanically sympathetic in my car beyond letting the oils get off the stops before increasing my rev range.

RDMcG

19,096 posts

206 months

Tuesday 21st August 2018
quotequote all
EVs will require less mechanical sympathy.
The scary part is they require much less servicing, the the problem in the future is that the service revenue on which dealers depend will be decimated........

Jayzee

2,376 posts

203 months

Tuesday 21st August 2018
quotequote all
TooMany2cvs said:
Mave said:
66mpg said:
Another point to consider: since the demise of brake pads with asbestos the friction material wears the disks much faster. We’re all going to be buying more disks than we used to.
It's probably been 20 years since they stopped putting asbestos into brake pads so I think we should be used to it by now! :-)
Longer than that - "Asbestos Free" was being shouted about in the mid-late 80s, and it's 20 years next year since they were completely and utterly banned (but that was irrelevant, since they'd long-since disappeared anyway).
I’ve still seen NOS brake pads for sale, which classic car owners seem to lap up as they’re more durable. Personally, I think they’re being a bunch of selfish s fitting them.

wst

3,494 posts

160 months

Tuesday 21st August 2018
quotequote all
Test driver said:
spookly said:
Driving in a way to conserve brake pads and disks makes Jack a dull boy.
Exactly. Rolling road blocks ffs; shameful.
Don't knock it til you try it. You'll be amazed at how often you catch up to people who are going unnecessarily slowly because they braked due to not looking forward enough to not need their brakes.

warch

2,941 posts

153 months

Tuesday 21st August 2018
quotequote all
I think DMF failure is often people doing things like labouring the car in the wrong (too high) gear which causes juddering or vibration.

I think regular good, hard application of the brakes is good for them, rear callipers especially are a sod for seizing on most cars, simply because they don't move enough. Modern car brakes are so good you never really brake really heavily as you'd ingest a kidney or something, so I usually pull the hand brake up and down a few times, or drive with it a few clicks on.

Disastrous

10,072 posts

216 months

Tuesday 21st August 2018
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Why would you not want to use your brakes?? Given that they are there, and consumables, why wouldn’t you want use the vehicle as hard as possible within the given limits?

a). It’s more fun
b). The money you save is irrelevant inside the total cost of vehicle ownership
c). It’s still more fun

I ride motorcycles so would say my reading ahead and planning is better than most car drivers but I would still wait until the 30 sign before I started slowing down, even though I probably saw it aaaaages ago wink

I wouldn’t say I was an especially sympathetic person though, mechanically or otherwise, I just don’t really care. I enjoy the sensation of acceleration and don’t really mind if it means having to replace bits here and there.

Redline88

381 posts

105 months

Tuesday 21st August 2018
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I think a lot of it also has to do with a changing ownership model. Not to start the PH hot topic of PCP vs lease vs outright purchase but in the past with the vast majority of people buying cars outright, they tended to keep them for a longer period and with less refined components, they would last as long.

Now when people have a fixed term agreement such as 24k miles over 3 years most of these components will last the initial ownership period and as such aren’t given as much consideration in daily driving.

DJP

1,198 posts

178 months

Tuesday 21st August 2018
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Mechanical sympathy is about smooth control inputs, letting the vehicle warm up and not riding the clutch.

Component longevity is about how and where you use the vehicle: Drive mainly on the motorway and brakes, clutches and suspension will last forever. Drive mainly in urban traffic and they won't.