Speedo

Post by **DiscoDave** » 12 Jul 2006, 17:36

it is old a worn, most of em are like that! how do you know its' out by 7mph?

Post by **Aidan** » 12 Jul 2006, 17:42

they are all out, generally overreport by 10% it's a deliberate design thing I believe.
GPS may not be totally accurate either

Post by **Flibbertigibbet** » 12 Jul 2006, 17:59

Mine is too ....actually drives about 5 mph faster than recorded on dial

Post by **"WEAZLECHIN"** » 12 Jul 2006, 20:10

just follow an artic on the motorway, he will be doing 56mph, then make a note!

Post by **Mocki** » 13 Jul 2006, 07:44

"WEAZLECHIN" wrote:just follow an artic on the motorway, he will be doing 56mph, then make a note!

unless its scottish, irish , tesco, asda, ect.......

limiters are 54mph, but vary on truck tyre size too!( old worn tyres at calibration time, new ones fitted after,?
Anywhere from 52-58 mph, so that wont tell you if you speedo is out will it?

Post by **shepster** » 13 Jul 2006, 07:46

What size front tyres are you using?

Post by **T2Andy** » 13 Jul 2006, 15:28

Think mine may be out as well, there is a 40mph limit bit of road on the way to work and I sit at around 65kph(40mph ish) and loads of cars overtake me so it must be out, same with other limits on other roads.

Post by **"WEAZLECHIN"** » 13 Jul 2006, 18:32

the stralis i drive at weekends is 6 months old, digital autocruise and sits at 56mph up hill and down dale, all day long, but the sad daf i was in last weekend sat at 60 all day. so follow a 6 month old iveco stralis if you see one !! tachos are calibrated every year.

Post by **T2Andy** » 24 Aug 2006, 13:58

Following up on this, did some tests round our local by-pass at the weekend, got the wife to drive in front up and down at various speeds and basically my speedo seems to be out by 15%.

So 40mph should be 65kph but actually have to do 75kph to be doing 40mph.

Is there any way of sorting this other than changing the speedo?