Speedometer Accuracy

[erikgeoff]

How accurate is the speedometer on the sv650?

[erikgeoff]

...'cause my speedo read a full buck this morning but, based on surrounding traffic, etc, it could not have been more than 90.

Mission control, I think we have a glitch.

[Dominus]

Why you riding 100 in traffic???? Even if it is slower than indicated...:squid:

[erikgeoff]

Yes, riding in traffic. 7am on the 8 lane in O.side. I was keeping up with traffic, passing the occasional, laying it on for the clear straights. But it wasn't like the doors were getting blown off of anybody...which is why I am asking.

...and yes: :squid:

[racinteach]

gps read 55 , speedo read 60 they all seem off by about 5 mph

[thor310]

Originally posted by racinteach
gps read 55 , speedo read 60 they all seem off by about 5 mph

5-10% as you go faster from what i've heard.

does that mean the odometer is off too? (it's not from comparisons to online maps)

[Zeus650]

Originally posted by Dominus
Why you riding 100 in traffic???? Even if it is slower than indicated...:squid:

i dont know where you ride, but on the major freeways around here, if you arent indicating 100 mph when there isnt much traffic, you are getting passed left and right.

[Dominus]

Originally posted by Zeus650
i dont know where you ride, but on the major freeways around here, if you arent indicating 100 mph when there isnt much traffic, you are getting passed left and right.

I ride on racetracks where those are acceptable speeds...any more questions?

[NiteQwill]

Originally posted by Dominus
I ride on racetracks where those are acceptable speeds...any more questions?
Hahaha... that's an awesome comeback... :p :D

[illustr8dman]

By changing to a higher profile front tire you will decrease the amount of error of your speedometer to I think like 1or 2 %.

[SVSRyder]

this is something the NHTSA really needs to crack down on... Speedometer Accuracy.

We did tests in the mid 90's on several manufacturers... and most of the vehicles (mechanical -or- magnetic) speed sensors were consistantly 10% off + or -. That's enough to get you a ticket by the truly anal cops out there.

NHTSA rules though govern in a very ambigous manner in saying that "essentially" that senors and displays must be within a "reasonable amount of certainty".

The manufacturers reply to this is that they cannot consistantly build a cost effective speedo sensor that is 99% accurate.

To that, I say what about the certified calibrations for police vehicles? Just laziness on the manufacturers part really.

[NiteQwill]

Can always buy a SpeedoHealer... I know a friend who has one and it works great... When he paces a car that is going the speed limit he actually is going at the right speed versus 7-12mph indicated, like before.

[newbie]

Originally posted by SVSRyder
The manufacturers reply to this is that they cannot consistantly build a cost effective speedo sensor that is 99% accurate.

To that, I say what about the certified calibrations for police vehicles? Just laziness on the manufacturers part really.

That's BS...at my work we use magnetic flow meters everywhere and they are more than 99% accurate. They aren't that expensive either....

[Darth Lefty]

If they can't be 99% accurate, then why are they all low by the same amount?

The idea that they can't report revs accurately when there's a crank position sensor feeding the computer is another favorite of mine.

[SVSRyder]

They are prolly low (I am thinking) because suzuki (in this case) is most likely using the "closest" speedo cable available so as to save on engineering a new one. Find a bike with the same gearing and a slightly smaller stock tire and you will find out which bike has the same part number for the speedo sensor or cable.

[TwistGrip]

When I rode Gixxers, we had this conversation on the Gixxer.com board, too. While we were all re-wiring the TRE and our ECU's and someone brought up speedo re-calibrating.

Here's the one I remember:

http://www.blackrobotics.com/yb_home.htm

Called the yellow box.

It's for all (?) electronic speedos so they can be recalibrated for tire size, factory error or gearing (on rear-pickup bikes).

I have a Sigma cycle computer hooked up to my front wheel and it has been set to the exact tire circumference. It's always showing about 2% less than the mechanical one on the dash.

Guess I'll do my oil changes every 1530 miles now.

Sheesh, math.

pieces,
Evan

[ZenRider]

One word - kinda - Speedohealer.

www.motomummy.com

You get the healer, and a plug and play harness. Instructions for programming are on the website - and they will print out a step by step card to program the healer after you give them a single indicated/actual speed, as from a GPS, or calculate based on gear changes, etc.

Its easy and it works, plus the new ones store your top speed ;)

[D.T.]

Just tested mine. I was doin' some freeway dronin' today (:-> I almost fell asleep) and to pass the time I put my ODO in trip mode and watched the mile marker signs. I consistently got 1.1 mile to every 1 mile actual. Which equals around 10% :-? . I also put a 16T countershaft sprocket on also. I dunno how accurate freeway mile signs are either.

Anyhow, I wanna get a speedohealer, but $100! Hmmm...

[dasesq]

I just did a little test with one of those side-of-the-road radar "your speed is" things.

at 40mph indicated it said I was going 37
at 30 mph indicated it said I was going 29

[smokescreen]

my speedo says 0........ no matter what. sometimes.... it's spot on.

[Rsimpson]

So why a speedo error at all? Why doesn't Suzuki just get it right to begin with??????

It doesnt seem to be 5 mph fast. It doesn't seem to be 5-10% as you go faster..it is more random than that.

My brother paced me in his car and his 65 was my 72 and his 80 was my 86....


Just random....random and annoying!

[RoninApache]

Is that even legal? I mean, if I were to be pulled over for speeding, but I don't really know how fast I'm going, and it's some flaw in the vehicle, aren't the manufacturer's liable in some way?

[Rsimpson]

haha I wish I could use that excuse! In the end its your hand on the throttle, no one elses.

Unless someone wants to prove me wrong.

[KAZ]

I borrowed a GPS and found my speedo is off 6-8 mph. I do math in my head, it's cheaper than a speedohealer.:D

[Tom]

Originally posted by Rsimpson
So why a speedo error at all? Why doesn't Suzuki just get it right to begin with??????

Because it accelerates the rate at which the odometer puts on the miles. The quicker the miles add up, the quicker the owner will feel the need to get a new vehicle. That, and they know people like to brag about how fast they went on their Chevy this or Suzuki that. Kind of like how clothing manufacturers purposely label size 8 dresses as a size 7. They make the consumers feel better about themselves.