speedometer is off by 10%

[colorider]

Re: Speedometer Accuracy?

Just wondering if anyone has checked their speedo accuracy with a GPS yet? In my experiance Japanese bikes seem to read about 10k faster than actual, mine seems to be out more than that, I can be doing 130km/hr with people still passing me, I keep forgetting to move my GPS mount from my other bike until I get on the road.

Just curious what everyone else is seeing out there.

Retro

I'm going to merge this thread with one on the same subject started a few days ago..........

 

[Jeff]

Yes mine is off about 5 mph at 60 also I found something on eBay that I was thinking about getting but I'll have to wait as I don't have the cash for it right now. You can adjust your speedo with it.

YAMAHA SUPER TENERE 2011 HEALTECH SPEEDO HEALER V4
Just search for it on eBay.

 

[robo86]

Today my S10 is 2 weeks old and I finally got around to checking (because I could not believe that traffic was moving at 85 on a local road.) Reading 88mph I am actually going 80 and reading 130mph I am going 120.

That's kind of shitty IMHO.

 

[Firefight911]

Today my S10 is 2 weeks old and I finally got around to checking (because I could not believe that traffic was moving at 85 on a local road.) Reading 88mph I am actually going 80 and reading 130mph I am going 120.

That's kind of shitty IMHO.

Why? Because the manufacturer is following the law that states a speedo can read up to about 10% fast but can not ever read slow?

 

[GrahamD]

Ok You's wingers asked for it...

Prepared to be bored shitless by facts.

5.2.5. The vehicle is tested at the following speeds:
Maximum design speed (Vmax) of the vehicle specified by the vehicle manufacturer (km/h)
Test speed (V1) (km/h)
Vmax ≤ 45 80 % of Vmax
45 < Vmax ≤ 100 40 km/h and 80 % Vmax
(if the resulting speed is ≥ 55 km/h)

100 < Vmax ≤ 150 40 km/h, 80 km/h and 80 % Vmax
(if the resulting speed is ≥ 100 km/h)

150 < Vmax 40 km/h, 80 km/h and 120 km/h
5.2.6.

Spreadsheet this suckers...

The speed indicated shall not be less than the true speed of the vehicle. At the test
speeds specified in paragraph 5.2.5. above, there shall be the following relationship
between the speed displayed (V1 ) and the true speed (V2).
0 ≤ (V1 - V2) ≤ 0.1 V2 + 4 km/h

And that's just the speedo. And the poor engineers probably have to take a great design and go through every part of a bike and dumb it down accordingly.

Then when that is finished it's off to the marketing department :'(

Then add to that that no customer is going to give a damn about that accurate swiss instrument that cost you $500.00 to purchase so you will get tyhe $5.00 job that is +/- 10% accurate over the range and it still has to read above the actual speed. On the other hand this refers to the MAIN speedo. If you have an
additional speedo (eg a supplementary digital speedo) than you can be as accurate as you like with that.

Now all this is Australian design rules, but we have a habit of following "worlds best practice" so it is probably just borrowed from someone else in the free trade zone of the day.

Anyone want to be an engineer

Cheers
Graham

 

[Bundu]

To me the issue is that it seems like the S10 speedo's are ALL 8% high, so they are accurate in the sense that the error is constant from bike to bike - I am quite sure the 8% could have just as well been 3% - All the BMW's I've had, had an error of about 3%.

The speedo healer would result in your mileage reading being lower than actual, which I also don't like, apart from the fact that it would set you back another ~$115

 

[GrahamD]

To me the issue is that it seems like the S10 speedo's are ALL 8% high, so they are accurate in the sense that the error is constant from bike to bike - I am quite sure the 8% could have just as well been 3% - All the BMW's I've had, had an error of about 3%.

I don't know what the reason is that they are all 8% high. Obviously in most cases they are pretty accurate instruments. It maybe a case of a conservative estimate of all possible OEM tire sizes, manufacturers claimed error margins on the speedo and possibly a bit of marketing department thrown into the mix.

If the speedo has to be 4km/h out at 40km/h by law, maybe they just apply the same error to the whole band, who knows or meybe it's a case of just designing the instrument for the worst Design rules so that if someone mixes up a batch they are not going to get a big recall problem.

Cheers
Graham

 

[Buckeye56]

I think GrahamD is on target regarding different tire diameters. On my 02 FZ1 the speedo was almost dead on with Dunlop Qualifiers. Whne I put a set of Pilot Powers on it now reads -2mph at 60 measured against a GPS. I know that this is not 100 percent accurate but it does show how a different brand of tire can change the accuracy of the reading. FWIW, my 05 ST1300 is worse than the Tenere while the wife's 96 PC800 is about the same as the FZ1. It doesn't bother me enough to do anything about it. I am never in that big of a hurry to get anywhere so if I forget to adjust my speed up to get closer to the posted limit it is no big deal.

And as Graham points out, cost does enter into the equation. Like it or not, these bikes were built to a price point, all goods, aside from luxury items are. To me this is a minor issue given the fact that Yamaha initially did not plan to sell the bike in the US at all. I am thrilled that they did! And just so we are clear, this is not meant to say that you should not have an issue with this, only that I don't.

YMMV.

 

[Checkswrecks]

There are two parts to it and Graham hit one with tire size. They must account for Yamaha buying any tire on the market to be able to deliver motorcycles. Car companies tend to own tire companies or have more control over the tires they are going to install, because they buy and install a LOT more of them. Ironically, the Euro brands tend to deliver so few motorcycles that they can better control what they are putting on and typically have less error, due to the same reason (configuration control) in reverse.


The second is the ramifications about the error going the other way. From a manufacturer's perspective, if the speedo is 0.1 mph low, they have a product that can not be sold. So it's pretty obvious what the manufacturers do.


Meanwhile, the T has the same error that I hate in most Jap bikes.

 

[glazier]

Being the owner of a DL650 Wee Strom, I soon learned about the inaccuracy of the speedometers on these bikes.
At least for the VStroms there was Raceratb Gauge Faces to replace the factory ones (20 min job) and made the
speedometer read very,very accurate.

Alas, we have digital speedometers, don't know what the fix is for them.

 

[Bundu]

I don't know what the reason is that they are all 8% high. Obviously in most cases they are pretty accurate instruments. It maybe a case of a conservative estimate of all possible OEM tire sizes, manufacturers claimed error margins on the speedo and possibly a bit of marketing department thrown into the mix.

If the speedo has to be 4km/h out at 40km/h by law, maybe they just apply the same error to the whole band, who knows or meybe it's a case of just designing the instrument for the worst Design rules so that if someone mixes up a batch they are not going to get a big recall problem.

Cheers
Graham

point taken, but Yamaha specifies only 2 tyres for the S10, so the variance should be controllable - If they were so afraid of recalls, why not make speedo calibration possible at dealer level?

 

[Kevhunts]

My S10 & my last bike (BMW) both indicate(d) 5 mph faster than my Garmin GPS.

My Toyota & my brother's Ford are both in sync with my GPS, so I feel confident my GPS is accurate.

Has anyone taken their bikes back to the dealer and asked them to correct the issue?

 

[Twisties]

My BMW seems to be worse than the Yammie, for whatever reason. I don't trust gps speeds very much. I use the radar sign posts they have installed all around here. Approaching at steady speed when I have an adequate gap in the traffic (ensure it's reading you and only you, they tend to read the fastest or most massive object). Driving straight at the sign post for a few seconds when getting the reading (eliminate parallax error). Making repeated runs at the same speed, and again at different speeds. My S10 speedo seems to be just about 3 mph high between roughly 25 and 60 mph. I don't see any difference in that speed range. Not sure this behavior can be described as a percent error. In contrast, the BMW speedo error clearly scales with speed. If we suggest that speedo error potentially has a scalable factor plus potentially a fixed error then it can be represented by our old friend

y = mx + b

In the case of my particular S10 it seems that m is zero or very small. So I get y = b in practice. I can live with that since I know what b is... 3 mph. Well, at least until I get some wear on the tires, or get those Heidenaus mounted.

 

[Heyder]

Recently I made a trip of the 3.800Km with another ST and a BMW GS800. Both STs were equipped with GPS. I realized that BMW showed only 2Km/h more that GPSs and STs showed 12Km/h more than GPSs. I have a Kia Mohave showing only 1Km/h more than GPS and a Toyota Hilux which has a difference of 3 km/h for more too. How can a motorcycle be less accurate? ::010::

I sent an email to Yamaha from Brazil claiming this inaccuracy. I answered mechanically saying that I should take the bike to a dealership ...

Nobody knows the procedure to adjust the speedometer of STs? ::002::

 

[Bundu]

yip speedo over reads 8% and odometer 2% - these number "are within spec", but sloppy IMHO

you can get a speedo-healer, but then your odo will be even more off (and affect your resale possibly)


............ now to wait for the guys to say these things are not important, and they are right, it's just sloppy.... ::007::

 

[stevepsd]

yip speedo over reads 8% and odometer 2% - these number "are within spec", but sloppy IMHO

you can get a speedo-healer, but then your odo will be even more off (and affect your resale possibly)


............ now to wait for the guys to say these things are not important, and they are right, it's just sloppy.... ::007::

Actually you have it backwards....

If you use a speedo-healer to fix the fast reading Speedo, your odometer will then read less mileage than you have actually gone.

In my case my Speedo read 7% fast and the odometer was 2% fast. After installing the speedo-healer, my speedo is now right-on and the odometer reads 5% slow.

 

[mobyfubar]

Put on Heidenau K60s last week. Now the speedo is only 3 mph off at highway speeds instead of 5 8)

 

[Bundu]

Actually you have it backwards....

If you use a speedo-healer to fix the fast reading Speedo, your odometer will then read less mileage than you have actually gone.

In my case my Speedo read 7% fast and the odometer was 2% fast. After installing the speedo-healer, my speedo is now right-on and the odometer reads 5% slow.

that's what I actually meant - odo was 2% off and now 5% off

 

[Checkswrecks]

I sure get tired of this thread coming back over and over, without people looking into why the error is there.

Vehicles conform to United Nations Requirement #39, which is called: UNIFORM PROVISIONS CONCERNING THE APPROVAL OF VEHICLES WITH REGARD TO THE SPEEDOMETER EQUIPMENT INCLUDING ITS INSTALLATION (See: http://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/r039r1e.pdf)

The speedo accuracy may be found on Page 8, Paragraph 5.3, which states: The speed indicated shall not be less than the true speed of the vehicle. At the test speeds specified in paragraph 5.2.5. above, there shall be the following relationship between the speed displayed (V1 ) and the true speed (V2). 0≤(V1 -V2)≤0.1V2 +4km/h

This formula is where your speedo INaccuracy is designed in.
Your dealer can't do a thing about it. Neither can Yamaha USA (or Canada/UK/AUS/etc) as an importer, which really is just a subsidiary that buys vehicles from a foreign manufacturer and then resells/distributes them.

The manufacturers for the US also have to account for NHTSA coming in with a measurement error, keeping with the requirement to NEVER display less than actual speed.

 

[Bundu]

I sure get tired of this thread coming back over and over, without people looking into why the error is there.

Vehicles conform to United Nations Requirement #39, which is called: UNIFORM PROVISIONS CONCERNING THE APPROVAL OF VEHICLES WITH REGARD TO THE SPEEDOMETER EQUIPMENT INCLUDING ITS INSTALLATION (See: http://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/r039r1e.pdf)

The speedo accuracy may be found on Page 8, Paragraph 5.3, which states: The speed indicated shall not be less than the true speed of the vehicle. At the test speeds specified in paragraph 5.2.5. above, there shall be the following relationship between the speed displayed (V1 ) and the true speed (V2). 0≤(V1 -V2)≤0.1V2 +4km/h

This formula is where your speedo INaccuracy is designed in.
Your dealer can't do a thing about it. Neither can Yamaha USA (or Canada/UK/AUS/etc) as an importer, which really is just a subsidiary that buys vehicles from a foreign manufacturer and then resells/distributes them.

The manufacturers for the US also have to account for NHTSA coming in with a measurement error, keeping with the requirement to NEVER display less than actual speed.

.... blah, blah, blah, but somehow, BMW do it better