Action buses vs Speed Cameras?

James-T-Kirk said :

The new one is electronic – the old one (in the garage of my house) is definitely mechanical

You must be referring to the old ‘Galaxy’ class there Jim.

(nerd alert)

Thoroughly Smashed said :

James-T-Kirk said :

Thoroughly Smashed said :

All a speedometer really tells you is how fast the driven wheels are turning.

I disagree…. I know of a small red VW beetle that measures how fast the front left wheel spins, while it is the back wheels that are bring driven…

Oh dear. Is this the new beetle or the original? The former would surprise me a bit, the latter… not so much.

The new one is electronic – the old one (in the garage of my house) is definitely mechanical

Troll-Sniffer, you’d imagine that what you say would be a fair appraisal and I’m not necessarily disagreeing with the reasoning. in my own experience over many years I’ve found that the majority of GPS units – including your hand held Garmin units will give an error between 2-4km/h and that’s in open country with high sat. counts. We’ve found that differential units linked to both satellites and the phone network give excellent accuracy but they’re an order of magnitude beyond the sort of product that finds it’s way onto people dashboards.

James-T-Kirk said :

Thoroughly Smashed said :

All a speedometer really tells you is how fast the driven wheels are turning.

I disagree…. I know of a small red VW beetle that measures how fast the front left wheel spins, while it is the back wheels that are bring driven…

Oh dear. Is this the new beetle or the original? The former would surprise me a bit, the latter… not so much.

Thoroughly Smashed said :

buzz819 said :

georgesgenitals said :

If you drive onto wet grass, put your car in second gear, rev it to the redline then drop the clutch, you’ll find that your speedo will be reading 80km/h but you will hardly be moving.

I dunno about that…. Have you tried it?

All a speedometer really tells you is how fast the driven wheels are turning.

I disagree…. I know of a small red VW beetle that measures how fast the front left wheel spins, while it is the back wheels that are bring driven…

buzz819 said :

georgesgenitals said :

If you drive onto wet grass, put your car in second gear, rev it to the redline then drop the clutch, you’ll find that your speedo will be reading 80km/h but you will hardly be moving.

I dunno about that…. Have you tried it?

All a speedometer really tells you is how fast the driven wheels are turning.

buzz819 said :

georgesgenitals said :

If you drive onto wet grass, put your car in second gear, rev it to the redline then drop the clutch, you’ll find that your speedo will be reading 80km/h but you will hardly be moving.

I dunno about that…. Have you tried it?

Yep. And yes.

la mente torbida said :

A couple of points….

using cruise control in traffic

Of course they were using cruise control – that way they don’t have to look up from their book that often while they are driving.

troll-sniffer said :

Clown Killer said :

I use GPS for a wide range of work related applications on a daily basis. there’s no way in hell that I would rely on a GPS based speed reading from anything you can buy that goes in you car.

It’s possible that your satnav is more accurate than your cars speedometre but simply because it gives a diferent reading to what’s on the dial doesn’t mean that it’s more accurate, it’s just a diferent reading.

Depends on the GPS and the conditions. A Garmin hand-held picking up 12 satellites with an accuracy of 4 metres (probably better), on a wide open road will be accurate to less than 1 km/hr no ifs no buts, especially if the speed test is over a suitably long distance.

A common mapping get me there GPS in an urban setting will vary quite significantly if there are trees and tall building about, but is almost guaranteed to be within 1km/hr on wide open roads like the parkway and most of the Monaro Highway.

Refutation complete.

But the satellites are MOVING!

georgesgenitals said :

If you drive onto wet grass, put your car in second gear, rev it to the redline then drop the clutch, you’ll find that your speedo will be reading 80km/h but you will hardly be moving.

I dunno about that…. Have you tried it?

Clown Killer said :

I use GPS for a wide range of work related applications on a daily basis. there’s no way in hell that I would rely on a GPS based speed reading from anything you can buy that goes in you car.

It’s possible that your satnav is more accurate than your cars speedometre but simply because it gives a diferent reading to what’s on the dial doesn’t mean that it’s more accurate, it’s just a diferent reading.

Depends on the GPS and the conditions. A Garmin hand-held picking up 12 satellites with an accuracy of 4 metres (probably better), on a wide open road will be accurate to less than 1 km/hr no ifs no buts, especially if the speed test is over a suitably long distance.

A common mapping get me there GPS in an urban setting will vary quite significantly if there are trees and tall building about, but is almost guaranteed to be within 1km/hr on wide open roads like the parkway and most of the Monaro Highway.

Refutation complete.

If you drive onto wet grass, put your car in second gear, rev it to the redline then drop the clutch, you’ll find that your speedo will be reading 80km/h but you will hardly be moving.

All of the chatter above seems ill-relevant because if the bus was speeding when it went past the camera, the driver will get a letter. Same applies for all of us regardless on how or what we perceive our speed is – Argue all you like it is the umpire (camera) that the court will believe.

As already pointed out, the speedometer in your car has been deliberately calibrated to read at a speed faster than you are actually travelling. The amount it is out will depend on the make and model of your car, the tyres and if your car has been modified. Using the cruise control makes absolutely no difference to the accuracy of the speedo, your actual speed will still be lower.

If you sit on 80kph by the speedo, you are likely to be travelling at a speed between 72 and 78kph, hence why the bus cruised past you. Most buses are speed limited to 85kph, but depending on the slope of the road can go faster. I can’t say I’ve ever come across a bus doing the 100kph speed limit, I have only seen them keep up with the traffic when the traffic is moving below the limit.

BenMac said :

How is it that ACTION Buses are able to keep up with traffic on the Parkway?

They’re not doing 15km/h under the speed limit, that’s for sure.

It seems that you are making the same mistake as the original poster. When you think you’re doing 100kmh along the parkway you are most likely only doing about 94kmh due to you speedo error. That is only 9kms more than what the bus is doing. On level ground the bus will definately be doing no more than 85kmh. Some buses will go a little bit faster down hill. Also, when accelerating, if the bus driver has his/her foot flat on the accelerator it may take a moment for the speed limiter to restrict the speed once 85kmh is reached. In this case the speed may go slightly beyond 85kmh but this will only be for a few seconds and the speed will gently go back down to 85kmh.

ConanOfCooma said :

Very Busy said :

All ACTION buses have speed limiters which limit their top speed to 85kmh. That is the maximum speed that the bus that went past you would have been doing on that level section of road.

How unusual. Doesn’t explain how the buses on the highway are more than capable of doing 100 in the signed 100 zone.

Are these buses on the highway ACTION buses? I didn’t no they had branched out.

How is it that ACTION Buses are able to keep up with traffic on the Parkway?

They’re not doing 15km/h under the speed limit, that’s for sure.

ConanOfCooma said :

How unusual. Doesn’t explain how the buses on the highway are more than capable of doing 100 in the signed 100 zone.

Certainly is unusual, every model listed on their website has a top speed of 85km/hr or less, artificially limited or otherwise. I wonder what’s going on there.

Very Busy said :

All ACTION buses have speed limiters which limit their top speed to 85kmh. That is the maximum speed that the bus that went past you would have been doing on that level section of road.

How unusual. Doesn’t explain how the buses on the highway are more than capable of doing 100 in the signed 100 zone.

I use GPS for a wide range of work related applications on a daily basis. there’s no way in hell that I would rely on a GPS based speed reading from anything you can buy that goes in you car.

It’s possible that your satnav is more accurate than your cars speedometre but simply because it gives a diferent reading to what’s on the dial doesn’t mean that it’s more accurate, it’s just a diferent reading.

JessP said :

My car is a 6 month old Golf and I am told the cruise control settings are spot on (it indicates the actual speed numerically not just relying on it about 80 km on the speedo).

Your car having an electronic speedometer doesn’t have anything to do with the calibration of the speedometer. The way you can test it is to time yourself through the “speedo check” section on Tuggeranong Parkway northbound between Hindmarsh Drive and Glenlock Interchange. I’ve driven unmodified cars along that section that indicated 100km/hr on the speedometer but were actually doing less than 90. Only one car I’ve driven had a factory speedo that indicated the actual speed and that was a private import.

JessP said :

The bus wasnt doing a 1 or 2 km/h more than me – it was more like 5-10km/h more – passed me at some speed. The speed camera was quite obvious so it wasnt that the driver couldnt see it.

All that proves is that in your judgement you were doing 5-10km/hr less than the bus, not that the bus was exceeding the speed limit by some particular amount. What Very Busy said above is correct, ACTION buses are limited to 85km/hr.

Hi Jess,

Regardless of the type of speedo (dial or numeric) the Australian standard stipulates that the speedo must not read over the actual speed and is allowed to read under actual speed by a certain amount (I’m not sure what it is off the top of my head). To ensure they are within these limits and to allow for vehicle modifications such as different wheel sizes between models all manufacturers have their speedo’s calibrated to under read by a small margin. For example an R32 Golf has different wheels than an FSi which would effect the speedo reading slightly. To allow for all models to use the same speedo components VW would build in a level of error which meets the standards. Your speedo will under read to some degree.

JessP said :

Dear Very Busy and Troll Sniffer. My car is a 6 month old Golf and I am told the cruise control settings are spot on (it indicates the actual speed numerically not just relying on it about 80 km on the speedo).

The bus wasnt doing a 1 or 2 km/h more than me – it was more like 5-10km/h more – passed me at some speed. The speed camera was quite obvious so it wasnt that the driver couldnt see it.

Doesn’t matter how old or new a car is, just how well the speedo works, my 94 BMW is spot on according to my GPS, a brand new Hilux was indicating a speed that was 10km’s slower than the actual speed, Most Commodores and Fords are maybe 2-3km’s slower than actual speed.

So if your speed is 2 or 3km’s slow and the bus was 4 or 5 km’s fast, then it would appear that the bus was motoring alongside you.

A couple of points….

using cruise control in traffic

speeding was the bus driver’s problem

Dear Very Busy and Troll Sniffer. My car is a 6 month old Golf and I am told the cruise control settings are spot on (it indicates the actual speed numerically not just relying on it about 80 km on the speedo).

The bus wasnt doing a 1 or 2 km/h more than me – it was more like 5-10km/h more – passed me at some speed. The speed camera was quite obvious so it wasnt that the driver couldnt see it.

Hi JessP

Agree with Very Busy (who can’t be that busy but that’s another thread)

Getting a GPS was an eye-opener for me. My car has the following real vs indicated speeds:

Actual GPS 50 Indicated 51
Actual GPS 60 Indicated 61
Actual GPS 70 Indicated 72
Actual GPS 80 Indicated 82-83
Actual GPS 100 Indicated 104
Actual GPS 110 Indicated 118
Actual GPS 120 Indicated 130+

A mate’s Falcon, a couple of years old, is within 1km/hr across the board.

It’s quite likely you were doing 77 or so, the bus was probably doing 85, (perfectly safely in its own lane) and as you gnashed your teeth you were probably un-necessarily causing those behind you to slow up.

You have made a very common mistake. Although your indicated speed is 80kmh, your actual speed is more likely to be something between 73kmh and 78kmh depending on what type of car you drive.

Factor in the tollerance margin of usually 10%, your speedo reading would more than likely need to be in excess of 90kmh before you would receive an infringement notice.

ACTION bus drivers ARE subject to the same road rules as everyone else and have received fines for breaking the law in the past.

All ACTION buses have speed limiters which limit their top speed to 85kmh. That is the maximum speed that the bus that went past you would have been doing on that level section of road.

I have a family member who’s an Action Bus driver and they do get picked up by speed cameras just like a normal vehicle, i’m fairly sure he said the driver on the route at the time loses the points, pays the fine though. As for whether Action Buses have to abide by the speed limit, of course they do..but they’re just like any other driver who also has to abide by the speed limit but doesn’t (except they’re carrying paying passengers).