Muppetz
Active Member
Reading another thread ref an indicated speed of 85mph on the motorway (and what that true speed would be..) got me thinking ... http://www.mbclub.co.uk/forums/showthread.php?t=54534
Surely manufacturers would always set speedometers to over estimate speeds, for 2 reasons :
1) So they can't be taken to court when you are caught doing 31 if your speedo says 30 (for example). ("It's the cars fault, it said I was only doing 30mph...) - They would need to build in some "margin of error" for this ?
2) If the speedo over reads, then does that mean that the miles completed over a period of time will also be over estimated ? If so does this mean that the mpg will appear slightly better than it should ? and also that services will happen slightly sooner than the should ?
i.e. if the speedo reads 100mph and I drive for an hour then the tripometer should also read 100 miles... If the speedo has been over estimating a real speed of 90mph then have I actually only done 90 miles ?
And therefore after 10,000 mile indicated have I only done 9,000 miles ?
So the manufacturers could claim better mpg, and have you in for service more often(or claim longer periods between services !)
Surely manufacturers would always set speedometers to over estimate speeds, for 2 reasons :
1) So they can't be taken to court when you are caught doing 31 if your speedo says 30 (for example). ("It's the cars fault, it said I was only doing 30mph...) - They would need to build in some "margin of error" for this ?
2) If the speedo over reads, then does that mean that the miles completed over a period of time will also be over estimated ? If so does this mean that the mpg will appear slightly better than it should ? and also that services will happen slightly sooner than the should ?
i.e. if the speedo reads 100mph and I drive for an hour then the tripometer should also read 100 miles... If the speedo has been over estimating a real speed of 90mph then have I actually only done 90 miles ?
And therefore after 10,000 mile indicated have I only done 9,000 miles ?
So the manufacturers could claim better mpg, and have you in for service more often(or claim longer periods between services !)
