What it is the error tolerance in a LR speedometer?

[Chucaro]

Under the changes previously flagged by the government, anyone detected traveling up to 10km/h over the speed limit will lose one demerit point. Ref HERE (http://www.news.com.au/couriermail/story/0,23739,25125766-5003402,00.html)

Than means that if the speedo of your LR shows 50 KPM and you are in a 50 kph and the radar detects 52 kph you are loosing 1 point demerit point?

How the drivers are going to know the precision of the speedometer in their car if it is not checked on the yearly inspection on the cars in NSW and there is not compulsory inspection in interstate cars?

Seems to me that it is another blunder from the dogooders or just to raise money :(

[rick130]

Defender speedos are generally 7-8% out, ie. with 'standard' tyres and 100km/h indicated you are actually doing 92-93km/h.

[29dinosaur]

mmm. sore point... have been 'done' twice in the last week at same camera.

First I didn't even realize, but notice came in post this am. Second, I saw the flash at same time as looking down at speedo which was reading approx 84kph (in 80zone). So am expecting second notice by end of this week... 3 points for under 15kph, over limit and $88.00 per pop. Grrrrrrrr. (North bound lane near Wollongong Uni. Boy there are a lot of speed cameras in the Illawarra).

So I reckon the D2 is pretty accurate. (Will check with my GPS some time).

[abaddonxi]

My 130 runs at 8% off. Checked many times with GPS and those roadside counters.

Dunno about the 110.

Simon

[aew849]

Lived in NSW 1998 to 2006 and always wondered why the speeding fines hit you with 3 points straight up....now they have finally come up with a plan for more revenue (coz they're broke) by reducing the points per low level speeding (WA has been doing this for yonks).

The rozzers can now do you 12 times vice 4 times for low level speeding, thus getting 3 times more money out of a driver before suspension.:nazilock:

WRT to speedo's...with 33" tyres on the 130 (BFG 255/85R16 MT's) the speedo is now spot on (+/- 1%). Previous smaller dia GY Wranglers had a 10%over read. These speeds were checked and averaged with a handheld 12 channel GPS on the 1700km trip to Karratha with the Wranglers, and from Karratha with the MT's.:)

[incisor]

my old girl is doing 100kph when the speedo tells me it is doing 83kph :p

great on the flats, sucks big rocks on hills :p

[Chucaro]

Just wonder about the time delay on the GPS and if it accurate enough to dispute a fine?

[spudboy]

How can you dispute the fine with a GPS?

Their equipment is presumably calibrated or certified on a regular basis.

[Chucaro]

How can you dispute the fine with a GPS?

Their equipment is presumably calibrated or certified on a regular basis.

If the GPS have history storage, you have a clean records and have a history of faulty radars used by the authorities you can have some weight to defend yourself in Court.
The court can order to inspect the radar in question.
I remember few years ago a light post in Hobart was detected of doing over 100 kph :eek:

[PhilipA]

I do not know where this idea of +-10% accuracy of speedos cpomes from.

I am sure that ADRs specify that speedos must have an accuracy of 0 to +10%.

That is why all speedos on new cars with standard tyres are optomistic.

You will never find a new car with a pessimistic speedo.

So will all the dreamers who think their speedos are pessimistic please get over it, unless they have changed their tyres of course. And then they should have the wit to know they have changed their speedo reading.
Regards Philip A

[hoadie72]

Under the changes previously flagged by the government, anyone detected traveling up to 10km/h over the speed limit will lose one demerit point. Ref HERE (http://www.news.com.au/couriermail/story/0,23739,25125766-5003402,00.html)

Than means that if the speedo of your LR shows 50 KPM and you are in a 50 kph and the radar detects 52 kph you are loosing 1 point demerit point?

How the drivers are going to know the precision of the speedometer in their car if it is not checked on the yearly inspection on the cars in NSW and there is not compulsory inspection in interstate cars?

Seems to me that it is another blunder from the dogooders or just to raise money :(
Don't forget that under the current laws you can potentially cop 3 points for doing 1km/h over the limit.

BWT I've never owned a car that's had the correct size wheels and tyres that's speedo reads under, they've always read over the actual speed.

[101RRS]

I do not know where this idea of +-10% accuracy of speedos cpomes from.

I am sure that ADRs specify that speedos must have an accuracy of 0 to +10%.



Only from about 2006 - prior top that the ADRs were +- 10% - that is where it came from - so in theory cars built prior to 2006 can have a designed discrepancy`+- 10%

Garry

[B92 8NW]

Inaccurate Speedos in Court (http://www.trafficlaw.com.au/speedos.html)



The current ADR prohibits any under-reading:
"5.3. The speed indicated shall not be less than the true speed of the vehicle. At the test speeds specified in paragraph 5.2.5. above, there shall be the following relationship between the speed displayed (V1 ) and the true speed (V2).0 ≤ (V1 - V2) ≤ 0.1 V2 + 4 km/h." This formula means that the vehicle's actual (true) speed must not be greater than the displayed speed. (Displayed speed minus true speed must be greater than or equal to 0, and less than or equal to 4kmh plus 10% of true speed). This means that if your vehicle's actual speed is 100kmh, the displayed speed is permitted to be anywhere between 100kmh and 114kmh.
Prior to July 2006 the ADR allowed ±10%. This means that cars sold new prior to 1 July 2006 could comply with the ADR even if the speedo under-read by 10%. Despite this being theoretically possible, due to the testing procedures and the reasons stated below it is unlikely to occur in practice.

[Tombie]

If the GPS have history storage, you have a clean records and have a history of faulty radars used by the authorities you can have some weight to defend yourself in Court.
The court can order to inspect the radar in question.
I remember few years ago a light post in Hobart was detected of doing over 100 kph :eek:

Or you could just... I dunno.....

NOT Speed :cool:

Its a voluntary tax after all.....

[Bushie]

Just as well ours reads 5km over then :D

The S1 is interesting as it reads 10mph over IIRC
The 2a is pretty accurate

Converting mph to kph is an interesting task for me :D
In the S1 because of the 10mph error I multiple the kph speed limit by 8...and that gives me close to what mph the speedo should be reading.
In the 2a I multiple by 6 ;)
Of course this all only gives a rough guide :D

At least out on the open hwy there is no way I'd be doing over 100kph in the series LR's :D

So lets see - 60kph speed limit X 8 = 480 mph
Yep I reckon you're pretty safe in the series :D:eek::D
:twisted::twisted::angel:

Martyn

[Chucaro]

How they can justify to book a person going at 53 kph on a 50kph zone in a car buit before 2006 :confused:

My point is that if they are going to implement a law like this, the roadworthy certificate should include an inspection of the speedo.

Lots of innocent and law obedient drivers are going to be book with the existing or proposed law, further more these type of laws should be standard across all the States

[hoadie72]

How they can justify to book a person going at 53 kph on a 50kph zone in a car buit before 2006 :confused:

My point is that if they are going to implement a law like this, the roadworthy certificate should include an inspection of the speedo.

Lots of innocent and law obedient drivers are going to be book with the existing or proposed law, further more these type of laws should be standard across all the States

You've missed my point. They already can pull you over for doing a couple over the limit. And do in WA and Vic.

How many cars out there with the right tyres and wheels read under anyway - pre or post 2006? I've never seen any!

[V8Ian]

How they can justify to book a person going at 53 kph on a 50kph zone in a car buit before 2006 :confused:

My point is that if they are going to implement a law like this, the roadworthy certificate should include an inspection of the speedo.

Lots of innocent and law obedient drivers are going to be book with the existing or proposed law, further more these type of laws should be standard across all the States

This is not a new law, motorist can and are being booked for 1k over the limit now. The proposal is that for 1k over you will lose 1 demerit point, now you lose 3 points for the same offence.

[vnx205]

With an older second hand vehicle there is another reason why the speedo might be pessimistic - non standard parts (other than tyres and such obvious things).

My Series III had standard 750x16 tyres and as far as I could tell, the diffs were standard.

However my speedo read 90 kph when I was really doing 100kph. The odometer read 93 with brand new tyres or 94 km with old tyres for every 100 I traveled. I checked it several dozen times including over hundreds of km on the Stuart Highway and always got the same result.

My best guess was that it had some speedo parts out of a LR that was intended to have about 650x16 tyres.

Since the engine in it when I bought it was from an early 1960s LR, I always thought that was a reasonable assumption.

[PhilipA]

My best guess was that it had some speedo parts out of a LR that was intended to have about 650x16 tyres.
Like the transfer case gear from a SWB for instance?
Regards Philip A

[Bushie]

The current ADR prohibits any under-reading:
"5.3. The speed indicated shall not be less than the true speed of the vehicle. At the test speeds specified in paragraph 5.2.5. above, there shall be the following relationship between the speed displayed (V1 ) and the true speed (V2).0 ≤ (V1 - V2) ≤ 0.1 V2 + 4 km/h." This formula means that the vehicle's actual (true) speed must not be greater than the displayed speed. (Displayed speed minus true speed must be greater than or equal to 0, and less than or equal to 4kmh plus 10% of true speed). This means that if your vehicle's actual speed is 100kmh, the displayed speed is permitted to be anywhere between 100kmh and 114kmh.
Prior to July 2006 the ADR allowed ±10%. This means that cars sold new prior to 1 July 2006 could comply with the ADR even if the speedo under-read by 10%. Despite this being theoretically possible, due to the testing procedures and the reasons stated below it is unlikely to occur in practice.That actually aligns pretty well with what I have been told by the local highway guys, they were working on 10% + 3kph over the speed limit ie 100kph would let you go up to 113 before being booked.

I think the fixed cameras operated by the (NSW) RTA are a different story though.

The new demerit point is for speeds < 15kph over the limit.

The Daily Telegraph says licence demerit points will be slashed from three to one for low-range speeding offences up to 15km/h over the limit under the changes to be announced by the NSW government on Monday.
Martyn

[vnx205]

Like the transfer case gear from a SWB for instance?
Regards Philip A
Would that have had the same overall gearing as a LWB but just a different speedo drive to allow for the smaller tyres? If so then that is probably the explanation since there were other signs that the vehicle had been assembled fom someone's spare parts bin. :p They must have done a good job though. It gave me very little trouble in all the time I owned it.

[vnx205]

That actually aligns pretty well with what I have been told by the local highway guys, they were working on 10% + 3kph over the speed limit ie 100kph would let you go up to 113 before being booked.

I think the fixed cameras operated by the (NSW) RTA are a different story though.

The new demerit point is for speeds < 15kph over the limit.

Martyn
Years ago when radar was still very new, a member of the police force who was the guest speaker at an Apex Club meeting told us that they when they were set up on the Hume Highway, they set the alarm to go off at 15 over the limit.

I asked him if that was because they got all the customers they could handle at that speed or because they were the people who most needed to be pulled up, but he didn't really give me a straight answer.

I suspect that it would have been because on the Hume Highway just out of Yass they would have had more customers than they could handle if they pulled up people who were only 5 or 10 over the limit.

I suppose with speed cameras and everything automated, that problem no longer exists, so they can grab as many as they want.

[Blknight.aus]

if you can prove your speedos accurate and you have the GPS logging turned on AND you have the recording increment set to per .5 sec AND the HDOP of the GPS is marked at less than 3m you can use it to beat a speed camera.

HOWEVER....

don't try this unless your absolutely certain that you're in the right, other wise you get the heftier set of fines AND the court costs....

[PhilipA]

Would that have had the same overall gearing as a LWB but just a different speedo drive to allow for the smaller tyres?

AFAIK yes ( but I am not a Series trainspotter)
Regards Philip A

[digger]

I remember few years ago a light post in Hobart was detected of doing over 100 kph :eek:

and as a result the light pole cannot hold for nor apply for a licence for 3 years....:D:D:D


Horries speedo is about 60km/h out....when Im doing 60.......
Vets speedo is 780k out...as in its in a box with me and he is waiting to be brought down to join it!!!

[dandlandyman]

When I first set up my 2A, I fitted 7.50R16s and a fully checked out 1408 speedo. I set it with a GPS to read about 2.5mph (4kmh) optimistic. Of course, with advancing wear on the tyres, it now probably reads even more optimistic.
In almost eight years owning it, and thirteen years driving, I have never been pinged speeding. I learned very quickly to get out of overdrive through school zones, though.

Dan.
69 2A 88" pet4, 74 3 109" pet4, 68 2B FC pet6.

[JDNSW]

Like the transfer case gear from a SWB for instance?
Regards Philip A

All Series Landrovers (except Stage 1 and a few very early 80") have the same diff ratio and the same speedo gears on the back of the transfer case.

However, there are at least a dozen different speedos fitted, and for the purposes of this discussion, the variable is tyre size, and specifically the speedos fitted as standard to swb and lwb. These assume a 7.50 tyre on the lwb and a 6.00 tyre on the swb. Fit 7.50s (as is commonly done) on the swb, and you need to fit a lwb speedo or your speedo will underread. Same problem if a swb speedo is fitted to a lwb.

For interest, some of the other factors that changed the speedo fitted:-

Six - went to a higher speed
S3 vs S1,2,2a - different cable connection
80" - smaller speedo
S3 and S2a after suffix D - warning lights in speedo
Kph or mph
Trip or no trip

John

[vnx205]

So if I understand you correctly, the most likely reason for my speedo and odometer in my Series III LWB being pessimistic is that it had the speedo from SWB.

IIRC the cable had the plastic clip to attach it to the speedo head.

It's all academic now as I sold the Series III a couple of years ago, but I often wondered what the explanation was.

[JDNSW]

So if I understand you correctly, the most likely reason for my speedo and odometer in my Series III LWB being pessimistic is that it had the speedo from SWB.

IIRC the cable had the plastic clip to attach it to the speedo head.

It's all academic now as I sold the Series III a couple of years ago, but I often wondered what the explanation was.


Yes. Plastic clip is correct for Series 3 (all models).

John

[dandlandyman]

I'm sure this has been listed somewhere before, but here are some ratio numbers for late S1 to S3. They are printed on the speedo face, either above the odometer or under the warning lights.

SWB S1 to S3metric: 1536 - suits 6.00x16 and 6.50x16.
LWB S1: 1500 - suits 7.00x16.
LWB S2 to S3metric: 1408 - suits 7.50x16.
Metric S3 LWB: 860 - suits 7.50x16.
Metric S3 SWB: 880 - suits 6.50x16.

My 2B FC speedo reads 1344 which should suit 9.00x16s. There are some others which I am unfamiliar with but these should help most people.

Dan.
69 2A 88" pet4, 74 3 109" pet4, 68 2B FC pet6.