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I was wondering, My speedo is off by at least 10% or more, and I heard something by correcting it you can put on a 200 tire on a stock rim. is that true, ans exactlty what size?
 

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I've been meaning to ask this question for a while and this thread reminded me. Why is the speedo inaccurate? If it is such a known issue, why does Honda not fix it? Does it apply to all years and all models?

Cheers

Jthree
 

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jthree said:
Why is the speedo inaccurate?
Just because...


lol: :lol: :lol:















If I were to make a wild guess....they have supplier of generic speed sensors (or whatever chip does the actual calculations) and they just pick one that gets them to within the legal error without having to design a whole new one.

My wifes Honda Accord is off by about 5%
 

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Poison said:
I don't know about the tire (seems like it may get you closer but I doubt it would make you accurate)
BUT
you can fix it with a speedohealer if it bothers you.
http://www.calsportbike.com/cgi-bin/sto ... gi?pid=800
I got one of these Speedo-Healers. My speedo is DEAD ON Accurate.
For the money - works great. Or you can just do the math in your head 10% reduction.

I got one because the speedo and Odometer are both off. SO if you decide to trade it in or sell it - the Odometer shows more miles than actual.

So your gas mileage is higher than actual. Sorry to burst your MPG Bubble.
 
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Though the speedometer may be inaccurate - and what is the big deal if it is? - the Odometer is accurate.

If you get the Speedohealer and fix the Speedometer, you will cause the Odometer to be in error.

Something called the " speedo to odo error ratio ".

Go to the Speedohealer website and read FAQ's #5 and #16

They explain it quite well.
 

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jthree said:
I've been meaning to ask this question for a while and this thread reminded me. Why is the speedo inaccurate? If it is such a known issue, why does Honda not fix it? Does it apply to all years and all models?

Cheers

Jthree
It's calibrated in Japanese and loses 8-10% in the translation from the fujitsushimi system to the American standard system....
 

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TexVtx said:
jthree said:
I've been meaning to ask this question for a while and this thread reminded me. Why is the speedo inaccurate? If it is such a known issue, why does Honda not fix it? Does it apply to all years and all models?

Cheers

Jthree
It's calibrated in Japanese and loses 8-10% in the translation from the fujitsushimi system to the American standard system....
Just Kidding, ya'll don't tear into me! :twisted:
 

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jthree said:
I've been meaning to ask this question for a while and this thread reminded me. Why is the speedo inaccurate? If it is such a known issue, why does Honda not fix it? Does it apply to all years and all models?

Cheers

Jthree
It's calibrated in Japanese and loses 8-10% in the translation from the fujitsushimi system to the American standard system....



oh man, too funny. Been to Japan several times and love it over there. Nice one!
 
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garysauctions said:
Though the speedometer may be inaccurate - and what is the big deal if it is? - the Odometer is accurate.

If you get the Speedohealer and fix the Speedometer, you will cause the Odometer to be in error.

Something called the " speedo to odo error ratio ".

Go to the Speedohealer website and read FAQ's #5 and #16

They explain it quite well.
Looks like you are on to something!!!!!!!

http://www.speedohealer.com/eng/faq.htm

#5. Will the SH calibrate both my speedo and odometer?

Yes, but it is not possible to calibrate them separately, as one speed signal drives both the speedometer and the odometer.

You can get 100% accurate speedometer AND 100% accurate odometer only on those bikes, which have zero "speedo-to-odo" error ratio (see FAQ #16) built-in, such as the Yamaha FJR1300.

On most bikes, if the speedo is calibrated to be 100% accurate, the odo will register slightly less miles. While this can be annoying in certain situations, one can always calculate the real distance easily after a long trip.

Alternatively, of course, you can get the factory default indication regardless of the used sprocket ratio: accurate odometer and slightly optimistic speedo.

With our on-line calculator, you can optimize the calibration value easily for either speedo or odo.

#16. What is the "Speedo-to-Odo error ratio"?

There is one speed signal which drives both the speedometer and the odometer.

However, the manufacturers make the display units such a way that the speedometers usually read high, while the odometers are quite accurate on stock vehicles.

Speedo to odo error ratio is the quotient of the indicated speed, and the speed which drives the odometer internally.

This error ratio is fixed in the dashboard logic, i.e. it's bike model specific and will be constant no matter what you change on your bike.

The speedo to odo error ratio is almost the same as the initial (factory) speedo error, considering that the odometers are usually accurate on stock vehicles.
 

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Mine is way off too, found out by using a GPS. Little more expensive than a speedohealer but effective.
 

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Do you know if this effects bikes in KPH? Cause this would kinda confirm my suspision. I have had my X now for about a month. I had a feeling my speedo was off about 10k. I would be doing 80K and still seem to be the slowest bike on the road. When I took it in for the 1000K service, the guy just looked at me like I was mental.
 

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harcosparky said:
garysauctions said:
Though the speedometer may be inaccurate - and what is the big deal if it is? - the Odometer is accurate.

If you get the Speedohealer and fix the Speedometer, you will cause the Odometer to be in error.

Something called the " speedo to odo error ratio ".

Go to the Speedohealer website and read FAQ's #5 and #16

They explain it quite well.
Looks like you are on to something!!!!!!!

http://www.speedohealer.com/eng/faq.htm

#5. Will the SH calibrate both my speedo and odometer?

Yes, but it is not possible to calibrate them separately, as one speed signal drives both the speedometer and the odometer.

You can get 100% accurate speedometer AND 100% accurate odometer only on those bikes, which have zero "speedo-to-odo" error ratio (see FAQ #16) built-in, such as the Yamaha FJR1300.

On most bikes, if the speedo is calibrated to be 100% accurate, the odo will register slightly less miles. While this can be annoying in certain situations, one can always calculate the real distance easily after a long trip.

Alternatively, of course, you can get the factory default indication regardless of the used sprocket ratio: accurate odometer and slightly optimistic speedo.

With our on-line calculator, you can optimize the calibration value easily for either speedo or odo.

#16. What is the "Speedo-to-Odo error ratio"?

There is one speed signal which drives both the speedometer and the odometer.

However, the manufacturers make the display units such a way that the speedometers usually read high, while the odometers are quite accurate on stock vehicles.

Speedo to odo error ratio is the quotient of the indicated speed, and the speed which drives the odometer internally.

This error ratio is fixed in the dashboard logic, i.e. it's bike model specific and will be constant no matter what you change on your bike.

The speedo to odo error ratio is almost the same as the initial (factory) speedo error, considering that the odometers are usually accurate on stock vehicles.

My speedo and odo are both off by the same amount of error. 10% high. I guess it's not etched in stone that one can be accurate while the other is off. But I just do the math and not worry about it.
 
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So I contacted Speedohealer and asked about this " Speedo-Odo Error Ratio " and how can I determine if the error is there and at what rate.

Their response " Buy a Speedohealer! " :lol:

I think I will stick with my original plan. Remove the Honda speedo console and just use my GPS. :lol:

I rarely look down at the speedo when riding anyway.
 

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TexVtx said:
jthree said:
I've been meaning to ask this question for a while and this thread reminded me. Why is the speedo inaccurate? If it is such a known issue, why does Honda not fix it? Does it apply to all years and all models?

Cheers

Jthree
It's calibrated in Japanese and loses 8-10% in the translation from the fujitsushimi system to the American standard system....
ROLMAO
 

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I put a 1300 rear final on my 1800-had both at the time. The rsult was this: my speedo was 0.2 off at all speeds but miliage showed to drop 3.2 mpg. It really didnt it was only corrected. Yes I did use the 1800 final in my 1300. Gave me plent more power but did lose some mpg due to engine turning more at the same speeds-I checked with my gps. Top speed did not change, lower gear allowed the engine to pull better- got closer to the limiter I guess
 
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