How accurate is the SV speedo?

Just wondered if anyone knows how accurate the SV speedo is? Maybe had GPS of some sort that is more accurate to compare it to?

I know that in my car, my speedo overreads by about 10%, is it a similar case on the SV? Is there any difference between pointy and curvy?

Originally Posted by skithepowder

Just wondered if anyone knows how accurate the SV speedo is? Maybe had GPS of some sort that is more accurate to compare it to?

I know that in my car, my speedo overreads by about 10%, is it a similar case on the SV?

yep, they all over read, a policeman/woman will let you know if your going too fast,

Confirmed with GPS that my '09 is 9% fast while on a trip around the States. Breakes it in to factors of eleven; 55=50, 77=70, etc. Don't know about the curvy though.

[kaivalagi]

I can confirm also from my GPS on the pointy, 77 actually 70, 66 actually 60 etc...I'd hazard a guess the curvy is the same

[andrewsmith]

rule of thumb for the overreads is 10%
There are some hondas and Yams that are 5%

My curvy seems to be Italian in this area, anything between 1% and 10%, but it was best part cured after a suspension refresh

[rictus01]

have a look at some of the top speed claims in one of the go faster threads, it'll give you the answer you seek......

[keith_d]

IIRC UK regulations require a speedometer to read between 0% and 10% above actual speed. Car manufacturers aim for about 5% over to allow for things like variation in tyre size.

I've not tested my bikes, but I wouldn't be surprised if they were somewhere near the 10% mark. Bike manufacturers have to allow for the fact that we'll fit all kinds of rubber to our bikes, so I'd expect plenty of margin to avoid under-reading.

Keith.

so does this mean as your tyre wears down your speedo gets more accurate? edit this would depend on where the reading was taken from, ie if of the drive then it wouldn't make any differance?.

[andrewsmith]

I'm sure over read it based on the Homoglated tire (in the curvy's case MEZ4) in run-in condition

[kaivalagi]

Originally Posted by bluefishman

so does this mean as your tyre wears down your speedo gets more accurate? edit this would depend on where the reading was taken from, ie if of the drive then it wouldn't make any differance?.

Whatever the little difference tyre sizing and wear will make it will make it no matter how the speedo readings are taken...whether from the wheel or sprocket rotation if the wheel diameter reduces you'll get marginally less distance and therefore less speed for the same rotation if that makes sense (and vice versa, if the tyre is a bigger diameter then the speed achieved is greater for the same rotation).

I'd be interested to know how much of an actual difference it would make though...I am thinking it's probably not worth even considering unlike the deliberate massive over read on the speedo itself...10% on the speedo compared to maybe 1% at most for tyre variations most likely...

edit: As a tyre wears the speed will reduce and therefore the reading will seem even more exaggerated, so less accurate....(I think...)