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I was wondering if since the spedo is of, is the odometer?

My spedo is about 3% high. So is my odometer also?

Any thoughts?
 

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Good question Paul, maybe you didn't need to change the oil as frequently ? ;)
 

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Don't know about the post '05 models, but the pre-'05 models were typically 3-4% high for Speedo readings, but only around 1% ODO. The modification that fixed the Speedo readings did not affect the ODO readings.
 

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dshealey said:
Don't know about the post '05 models, but the pre-'05 models were typically 3-4% high for Speedo readings, but only around 1% ODO. The modification that fixed the Speedo readings did not affect the ODO readings.
My 07 speedometer is about 5% high. 60 MPH on the GPS is 63 MPH on the speedo. I haven't done a precise check on the odometer, but it appears to match the GPS pretty closely. I haven't run far enough to get a high resolution comparison, but I suspect it is in the 1% range as it isn't noticeably different over several miles. However, a 1% difference is only 0.1 over 10 miles so it takes a while to detect that with any accuracy. I will have to do a more exhaustive check next summer.
 

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The speedometer on my 2005 is about 8% high as per my Garmin Zumo 550 GPS. However, the odometer is real accurate. I have done 600 mile days and the odometer would match within a couple miles the readout on the Zumo.
 

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Just today I was thinking I'd had enough with the speedo error. I think mine is around 10%. At 70 it reads around 76-77. What is the fix?

I have not checked the odometer, but my MPG rating on the trip computer is very precise. Never more than .3 MPG off.
 

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calvarez said:
Just today I was thinking I'd had enough with the speedo error. I think mine is around 10%. At 70 it reads around 76-77. What is the fix?

I have not checked the odometer, but my MPG rating on the trip computer is very precise. Never more than .3 MPG off.
Try this post!
 

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Wait, so basically, we're just installing the optional "make the speedo read accurately" jumpers that the factory left out?!? WTF?
 

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Several theories on this Carlos. One of the theories is that by making the speedometer indicate fast you will be less likely to get a ticket. However, what I have found is that when I use my GPS the error on the speedometer drives me nuts. So I have memorized the difference for the indicated speed vs the actual speed and build in the difference when I ride. I probably should just change the jumpers........

My Ford pick up speedometer is off in the other direction. i.e. it reads slow. The rule for driving the pickup is to NEVER EVER EVER exceed the posted speed or a ticket is likely.

I prefer the BMW error!

Loren


calvarez said:
Wait, so basically, we're just installing the optional "make the speedo read accurately" jumpers that the factory left out?!? WTF?
 

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wa1200lt said:
Several theories on this Carlos. One of the theories is that by making the speedometer indicate fast you will be less likely to get a ticket. However, what I have found is that when I use my GPS the error on the speedometer drives me nuts. So I have memorized the difference for the indicated speed vs the actual speed and build in the difference when I ride. I probably should just change the jumpers........

My Ford pick up speedometer is off in the other direction. i.e. it reads slow. The rule for driving the pickup is to NEVER EVER EVER exceed the posted speed or a ticket is likely.

I prefer the BMW error!

Loren
I am with you Loren, I get complacent about the error and try to build in the extra speed. Having had too many friendly conversations with LEOs, I now pay close attention to the GPS or ride the indicated speed on the speedo. I get cages tail gating me at times, but I can't afford any more tickets and lawyer fees.

I reviewed the link on the jumper change and I think I will fore go that procedure. My eyes are too weak and my hands too shakey :eek:
 

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calvarez said:
Wait, so basically, we're just installing the optional "make the speedo read accurately" jumpers that the factory left out?!? WTF?
What I have read before is that most if all countries have laws that require the speedo to NEVER read low, but are allowed up to 10% high. BMW just takes the safest way and sets them high. There are several calibration jumpers on the chip for the pre '05 bikes, we just add jumpers to calibrate more accurately than the BMW factory installed jumpers. Some have had the B and C jumper addition cause their reading to read slightly low, so removed A to correct it back up about 1 MPH.
 

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So is the first mod *exactly* 10%, or does it vary? I'd rather avoid taking the bike apart twice.
 

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calvarez said:
So is the first mod *exactly* 10%, or does it vary? I'd rather avoid taking the bike apart twice.
The pre '05 speedo circuit is an analog conversion from the digital signal the speed sensor puts out. There is no perfect converter (in the price range a manufacturer would pay for a speedo), so it has to be calibrated. That is why there are several calibration inputs to the chip. So, there is no way to guarantee any "exact" calibration factor, it has to be done by trial and error. However, almost everyone has found that adding the B and C jumpers comes very close without any further work.

The ODO circuit does not use analog conversion, and digital to digital is always pretty exact, therefore they did not put any calibration feature on the board for the ODO. The ODO still may not be exact though, as tire diameter affects it considerably as the tire diameters vary manufacturer to manufacturer, pressure variations and wear change them even more.

You will likely never get an exact reading on either the speedo or ODO, and even if you do for a short time, it will not stay consistent as tire variations occur.
 

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And after '05, you are stuck with the speedo reading about 4 MPH high once you are going over 30 Mph, and the GPS is dead on. Most of the time, I try to stay under 20 mph high on good open roads :histerica

However, in Wyoming, Utah and in the rural ends of Idaho, I try to stay under 30 Mph high.

And in Pennsylvania, I try to stay on the money to avoid handing over money to the cops.

It's sort of a toss up, but I also think that Idaho is among the most conservative with regard to the speed they post for curves, and this is from the perspective of riding two-up on an LT.

Bill
 

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I don't know if it will work on the '05 & up bikes , but on my'02 if I get up to speed ,then set the cruise control . Put the computer in MPH , then hit the reset . It will give me just about the exact speed im going .... It works on my'10 Adventure too ...
 

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I agree. It works the same on my '01. It's the digital to analog conversion that feed the analog guage on the dash that's off. The one onthe BCS gives average mph which is fine if you are using the cruise control.

Loren

Patric said:
I don't know if it will work on the '05 & up bikes , but on my'02 if I get up to speed ,then set the cruise control . Put the computer in MPH , then hit the reset . It will give me just about the exact speed im going .... It works on my'10 Adventure too ...
 

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My speedo is off about 3% but the odo is right on. Have checked it with GPS, mile signs and the bikes computer.
 

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As of 1997, Federal standards in the United States allowed a maximum 5% +/- error on speedometer readings. If the speedo is off more than that, the manufacturer is required by law to fix it. I am also pretty sure that age and milage won't matter. By that I mean even if your bike is out of warranty (Provided there are no aftermarket modifications) they have to fix it. It has been my experience the manufacturers always error on the high side which also takes into account eventual wear over time.

The following is copied from another site:
GPS devices are capable of showing speed readings based on how far the receiver has moved since the last measurement. As the GPS is an independent* system, its speed calculations are not subject to the same sources of error as the vehicle's speedometer. Instead, the GPS's positional accuracy, and therefore the accuracy of its calculated speed, is dependent on the satellite signal quality at the time. Speed calculations will be more accurate at higher speeds, when the ratio of positional error to positional change is lower. The GPS software may also use a moving average calculation to reduce error.

GPS data has been used to overturn a speeding ticket; the GPS logs showed the defendant traveling below the speed limit when they were ticketed. That the data came from a GPS device was likely less important than the fact that it was logged; logs from the vehicle's speedometer could likely have been used instead, had they existed.
 
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