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Comment by landgenoot | Hacker News Reader

Such an indicator is mandatory in the European Union.

> Vehicles of category M 1 with a reference mass not exceeding 2 610 kg and vehicles to which type-approval is extended in accordance with Article 2(2) of Regulation (EC) No 715/2007 which are fitted with a manual gearbox shall be equipped with gear shift indicators in accordance with the requirements of this Regulation and its implementing measures.

https://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:...

It is mainly a fuel efficiency measure. It also tells the driver when to shift up or down.

Example of the indicator: https://www.researchgate.net/profile/Kerry-Malone/publicatio...

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How completely unnecessary. You know what gear you shifted in because you shifted it in in the first place. If, once in a long while, you shift different gear, you notice imediatelly as you release clutch. If, once in a while, you forget to shift next gear, the motor will scream at you sooner than you notice the indicator.

And those people not being able to utilize all those "physical" indicators because of being new/bad drivers or being distracted wont notice this small number regardless of where it shows. Just more electronics in cars that desperately need to be getting rid of those...

The only instance of where confirmation of selected gear is usefull is when shifting into Reverse, and that is already acompanied by a beep.

The law isn't about telling you what gear you are in, it's about telling you when to shift up a gear (I'm not sure it's required to show downshifts, at least the few cars I've driven - all in the UK - only show up shift recommendations).

It's a little thing on your dashboard that pops up an up arrow and the number of the gear you should change to (and down arrow in cars that do support that).

And it's helpful because a) different cars have different engines/gear systems such that you can't learn a universal rule of "always move from gear 2 to 3 at X speed / Y RPM", and lots of people aren't good at knowing the most economical point to change into each gear even for their own car, so having the manufacturer program it in does help. I no longer pay attention to it in my car, as I've either shifted a second before it would have shown on the dashboard, or I've purposefully not gone up a gear because at that moment I care more about ability to accelerate for some reason than about being as economical as possible. But those tips were useful in helping me learn the ideal gear changes in my car without having to read up about its RPM sweet spots etc, and useful for anyone who I lend my car to who isn't familiar with the brand/model.

> "If, once in a while, you forget to shift next gear, the motor will scream at you sooner than you notice the indicator."

True if you're just thinking about not fucking up the engine, but not true if you're thinking about driving economically which is the point of the law. My car for example (a small hatchback, 1L turbo engine) gets best economy (and therefore suggests the gear changes) by upgearing when it's around about 2k RPM (not exactly, and varies by which gear), but the engine could comfortably go to 4k RPM without any screaming at all (iirc redlining is something like 6k-7k, and engine sounds fine until fairly close to that).

Upshifting at 2k RPM while accelerating is a fast way towards destroying the engine (especially the rod bearings and the dual-mass wheel) in less than 100 kkm. And I bet those upshift indicators don't take into account the temperature of the oil, do they?

Most car manufacturers don't care about longevity of their cars because they have no interest in that and EU doesn't care either. The manufacturer cares about you buying a new car every few years and EU cares about good results in some unrealistic emission tests in lab.

> "Upshifting at 2k RPM while accelerating is a fast way towards destroying the engine"

My professional driving instructor a few years ago, my car's manual and dashboard recommendations, and my two friends who work in (UK) car repair garages all disagree with you.

But I know very little about cars myself, so I can't really argue the point - but maybe there's a difference between the cars you're used to driving and my small 1L turbo engine 6 gear harchback?

My car is 9 years old with no problems yet so I can't speak to longevity of the engine beyond that, but have confirmed that following the car's guidance rather than letting the revs go higher before upshifting does give me much better petrol economy.

(And the dashboard recommendations definitely are more complex than "at X rpm recommend gear change", eg driving up steep hills the recommendations come later than when driving flat - no idea if it's taking oil temperature into control, but I also have no idea how to take that into control if I'm choosing when to gear shift...)

edit: oh, I have been told in the past that until the oil warms up from 10-15min driving that you shouldn't push the car, including not going to high revs, but nothing more specific than that general advice.

Two of my friends who had their bearings and double-mass wheel replaced in their cars around only as little as 100 - 150 kkm (one TSI another TDI) disagree with them.

The lower the RPM, the higher the momentum needed to keep the car accelerating nicely. High momentum = more vibration and faster wear. Low RPM means also worse lubrication. That's why turbo-charged and downsized "eco friendly" engines are way less durable than traditional NA engines. Not sure if they could be called "eco" at all because of this.

Assuming you aren't recommending always pushing to the red line before shifting up a gear, what makes you so confident that my car must have a higher ideal shift point than ~2000rpm, is there some rule of physics that prevents engines being made to optimise around that point?

Anecdotally I don't feel any difference in the gear shifting whether I upshift when the dashboard suggests or if I don't do it until, say, 4000rpm (though obviously do notice the different in the driving before the gear change), however if I shift up at lower revs than the dashboard suggests then I do feel a difference in the gear change itself and how easily the car seems to start in the next gear up.

Like I said, I'm not remotely qualified to speak on this subject but I'm also finding it very hard to believe you're correct (at least, correct universally for all manual cars), so I'm going to try to do some digging around for more info.

Heeeh. I drove mostly manual car (since it tends to be the "default" here in France), most of which did not have a indicator (they predated the law). I got to say, having one is still nice. In cities, where you change gear a lot, it means you still get to see the road if you ever get confused about which gear you are in (yeah, yeah, shouldn´t happen, bad driver, whatever, it does happen). But mostly, it is for the downshift / upshift indicator which is usually tuned for eco driving. Knowing when to shift by feel is usually very easy, but knowing the exact point for optimizing fuel consumption is harder, especially because it can change depending on the car. So having the indicator suggestion is nice.

> How completely unnecessary.

I think you mis-typed "I find this unnecessary".

It's additional information, located in the area on your display that you should be regularly scanning, as opposed to the gear lever that you can check by hand but should probably not be regularly (nervously?) checking.

I drive a euro 6 (forward) gear vehicle, and the ratio delta for gears 5 and 6 is really quite subtle. With even moderate music playing, I won't hear the 'motor screaming' if I forget to pop back up to 6 after being in 5 for some hill climbing, for example.

Anyway, this isn't a manufacturer's video, it's a fun little arduino project, so you don't need to be angsty about excessive electronics in cars. (I think that boat has well and truly sailed, in any case.)

Btw, my car does not beep when I change gear to reverse. If it did, I'd definitely be cutting some wires.

I expect that some people think what they find useful, and what their local regulations dictate, are the same for everyone else across the planet.

Yeah... unfortunately, they just show you the gear you should switch to, not the gear you're currently in (although that information is obviously available). So much for keeping your eyes on the road as much as possible...

The photo shows the current gear (3) and an indicator that the driver could shift up (the arrow pointing upward).

Must be model dependent. All the cars I've owned with physical gear levers and gear shift indicators show the recommended gear, not current.

No, the number is the current gear. The arrow in front of it indicates whether you should shift up or down

It's dependant on the make/model.

In all 4 manual cars I've driven (all sold in UK, so maybe different to rest of Europe?) they show an arrow and the number of the gear you should change to. Nothing on the dashboard about current gear (except in the automatic I've driven, which of course doesn't need to tell you when to change gears).

Every car I’ve regularly driven (typically European) has shown current gear, and an arrow for which direction you should be moving.

When was this law passed? I don’t have that on my 2012 Aygo.

1 nov 2011, but this is a type-approval requirement.

> Type approval describes the process applied by national authorities to certify that a model of a vehicle meets all EU safety, environmental and conformity of production requirements before authorising it to be placed on the EU market.

So your 2012 Aygo has probably been type-approved before that date.

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