[puchika]

Between my GPS and those drive-by police speed signs on the side of the road, my 696's speed seems off by 4-5 MPH. While those two sources may not be the most accurate way to find my true speed, it's consistent. Could changing the front sprocket to 14T have thrown off my speedo? I'm wondering if my odometer is off too.

TIA

 

[Duki09]

Like you said, those aren't the most accurate ways to check your speed.

I never passed one of those road side radars that were even close to being accurate.
I also believe GPS will only give a close estimated speed, but not an exact.

So I wouldn't rush into believing your speedometer is off ONLY because your GPS and road side radar signs aren't accurate.

 

[Winchester Boy]

The pickup for the odometer is on the rear rotor so changing the front sprocket won't hurt.
The speedo is off, I think 7-8 percent?

 

[drums4money]

The pickup for the odometer is on the rear rotor so changing the front sprocket won't hurt.
The speedo is off, I think 7-8 percent?

Yes they are optimistic, and if you get a ticket, they've really got you.

Your GPS should be accurate. You can even wire up a cheap bicycle computer & check your % of error @ 50mph.

 

[st2lemans]

In the manual of my 999R, it states that the speedo is typically 8% high.

And this seems to be correc, same for my SS1000DS

Ironically, my ST2 with analog speedo seems to have 0% error, based on riding past the same "your speed is" indicator at the same indicated speed.

Tom

 

[Winchester Boy]

I just live with it and allow for it.
I don't look at the speedometer very much anyway.

 

[KF6VGZ]

Between my GPS and those drive-by police speed signs on the side of the road, my 696's speed seems off by 4-5 MPH. While those two sources may not be the most accurate way to find my true speed, it's consistent. Could changing the front sprocket to 14T have thrown off my speedo? I'm wondering if my odometer is off too.

TIA

I posted the same thread after having the 14T sprocket put on. The sensor is at the back wheel, so they say it has no effect on the speedo error reading. And yes, confirmed via GPS that it's off at least 5mph at 65mph. :think: But the odometer still reads correctly...checked that with the mile markers on the side of the road. :abduct:

 

[Brackstone]

I have a Garmin Nuvo GPS and it is 100% accurate.

I know this because I take it in the car with me as well and when my Car Speedo says 70Mph my Garmin says 70Mph.

 

[Scissors]

Both the 696 and the 1100 have the same speedometer hardware. In the 1100 manual it specifically states:

“Speed” indicator
This function enables display of the motorcycle speed.
The dashboard receives actual speed value (expressed in km/h) from the control unit and displays the value increased by 8%.

So the displayed value is 8% higher than actual. That would mean your real speed is 7.4% below indicated. So your actual speeds versus indicated are:

Indicated = Actual
25 = 23
55 = 50.9
65 = 60.2
80 = 74
100 = 92.6

My Yamaha has about the same error, so I use the following memory trick:
Subtract 8 from 100, 6 from 75, 4 from 50, 2 from 25.

 

[puchika]

The 696's manual doesn't have that info, but if it's known, why don't they have the bike's computer adjust for it?

Both the 696 and the 1100 have the same speedometer hardware. In the 1100 manual it specifically states:

“Speed” indicator
This function enables display of the motorcycle speed.
The dashboard receives actual speed value (expressed in km/h) from the control unit and displays the value increased by 8%.

[\QUOTE]

 

[Brackstone]

Just to chime in I had the ability to play with one of those Radar Guns on the road that display your speed and the speedo on my monster is 100% accurate, I was very surprised. Either that or the Radar Detector was off too

 

[Scissors]

The 696's manual doesn't have that info, but if it's known, why don't they have the bike's computer adjust for it?

The bike's computer does adjust for it. The computer itself takes the actual speed and adds 8%. The dashboard computer knows your real speed, but it increases that number by 8% before displaying it.

This is done on purpose. Federal regulations forbid speedometers from reading below actual speed. Manufacturers deal with this by purposely adding speedo error. There was an article a few years back in one of the major automobile magazines where they mentioned that BMWs, for example, had the most error and GM the least (which isn't actually a good thing.)

The 696 manual does, in fact, state this as well. It's on page 19 of the 2009 Monster 696 English manual.

 

[Scissors]

More on speedometer accuracy...

European Union Directive 2000/7/EC set the requirements for speedometer accuracy.

There are two main requirements when tested:
1. That indicated speed is never below actual speed.
2. That indicated speed is never above 110%+4 km/h of actual speed.

For actual production motorcycles and motor tricycles, the upper limit increases to 110%+8 km/h (but remains 110%+4 km/h for mopeds).

So for a production motorcycle rolling at an actual 80 MPH, the indicated speed can't be below 80 MPH, and can't be above 92.97 MPH.

As this upper limit is 16.2% higher than actual, a built-in 8% error puts the Ducati motorcycle firmly in the middle of the legal range at highway speeds.

Link: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0007:EN:NOT