Wrong Speedo

Reporter: Graeme Butler

Slow drivers are hitting back and they say they're not to blame for holding up traffic it's their shonky speedos out by 10 12 sometimes as much as 16 kilometres an hour. Aleasha Turner from Brisbane recently bought a new Nissan - she says almost straight away she started copping abuse from frustrated drivers behind her. "I was in the 110 lane doing 110 down to the gold coast and I had other drivers sitting right up my rear and I'm thinking I'm doing the speed limit back off"

But her speedo was wrong - out by almost 10km an hour. "My husband pulled out his GPS and he did a speedo check on it and it was that was when we realised it was about 9 - 10 kms under""I don't' know if they're speeding I've got nothing to gauge it with my speedo as far as I'm concerned they're speeding but maybe they're no maybe my speedo is giving me a false impression" Fred Mackay in Perth also has a new car - a Rav 4. He saw today tonight's story on slow drivers and the penny dropped maybe it wasn't him but his car he checked his speed with a GPS and bingo.

We decided to test Fred's car - to see just how far out his speedo was, Dan Pitic is an automotive engineer. "Hi Dan so this is the testing gear how accurate is this going to be to tell us fast we're travelling? Well the equipment is capable of measuring distance say one kilometre as precise as 50 millimetres so that very accurate very accurate" It's not long before the problem with Fred's speedo becomes apparent. "Sixty this says you're doing 54 so 6 under the limit even at 60 so there's your 10%. That's 80 now this says you're doing 73 there's' a slight variation on the needle but you're significantly under the speed here"

To double check the accuracy of the testing equipment - Dan has also used a hand-held radar similar to those used by police. "So he was doing 70 what are you reading him at now so it's 64 63 62 so that's 10% double proof there 10% under and it's normal and it's normal because it's in line with the what ever the ADR requires" ADR is the Australian Design Rule and it's the law determining how accurate speedos need to be believe it or not as long as they don't under read. They can be as much as 16 km/h out if you're travelling at high speed, the rule says above 10% plus 6km is acceptable. .That means your speedo could say 110 and you're actually doing 84 think you're doing 60 it could be only 48.

"Fred, so what did you make of that there - well I feel much more confident at least it wasn't my imagination. So it was about 10% on average wasn't it about 10% confirms my original thoughts there was something not right as far as the reading on the speedo"And remember you can be fined in some states for driving too slowly. In WA you can only be fined $50 on the freeway if you're doing 20 or more under the limit.

- In NSW it's not specific but you can be fined if your slow driving is considered a risk to safety

-South Australia is much the same as NSW

In Queensland it can get nasty with a fine of up to $2000 if you're driving abnormally slow for example 20 in an 80 zone

And in Victoria it's the same as Queensland though the fine is a friendlier $238.

If you have ever been booked for travelling too slow, let us know : tt@7perth.com.au