Author |
Message |
Wbrisett
| Posted on Tuesday, September 09, 2008 - 05:56 pm: |
|
After reading one of the threads on the ECM reflash, it got me to wondering how accurate the Uly speedometer really is. If I'm going 70 MPH according to the Uly speedometer, my GPS shows speeds closer to 63 or 64. I might add that in two different cars if they say I'm going 70 MPH, the GPS is within one MPH of that. I guess there is one bright side to this though, I rarely have to worry about speeding if I'm within 5 MPH over according to the speedometer. Anybody else measure their speeds with a GPS and see a large discrepancy? Wayne |
Atoms
| Posted on Tuesday, September 09, 2008 - 06:07 pm: |
|
I see a difference, but not that large. At 70 indicated on my '07 Uly, my Zumo says 67 or 68. I finally mounted the Zumo just when I decided to slow down a bit in general. It works out great. I can go just as fast as before, but it turns out that I'm going slower, so I don't actually have to slow down. |
Svh
| Posted on Tuesday, September 09, 2008 - 06:50 pm: |
|
70 shows at 64-67 for me using my installed today Zumo GPS. Glad I am not the only one that noticed this |
Lost_in_ohio
| Posted on Tuesday, September 09, 2008 - 09:53 pm: |
|
I think the general belief is the the engineers may have done it on purpose. Made the speedo read a little fast. There was a thread about the XT speedo was accurate and after an ecm update it read a tad faster than the GPS. Call it a safety margin. |
Strmvt
| Posted on Tuesday, September 09, 2008 - 10:12 pm: |
|
ya mine is off to by 5 after I hit about 35mph |
Hoon
| Posted on Tuesday, September 09, 2008 - 10:49 pm: |
|
Mine is roughly 5 mph out round the scale too ('06 XB12X),I marked the accurate speeds (according to my Twatnav) on a piece of masking tape on the speedo glass. I stopped at 70 mph 'cos after that it's all naughty so who cares after that?! Yeah,I think it's deliberate too,for safety reasons-my Peugeot 206 (car) speedo is out as well. |
Paul56
| Posted on Wednesday, September 10, 2008 - 12:45 am: |
|
Dare I ask...... Twatnav? |
Zynthaxx
| Posted on Wednesday, September 10, 2008 - 04:35 am: |
|
At least here in Europe, I remember reading that the instrument is not allowed to err on the low side of the actual speed, and that the allowed error in the other direction is up to 110% of your actual speed + 4 km/h |
Wbrisett
| Posted on Wednesday, September 10, 2008 - 05:55 am: |
|
I stopped at 70 mph 'cos after that it's all naughty so who cares after that?! Not here in Texas. Parts of I-10 in the western part of the state are marked for 80 MPH (the fastest in the country). I can remember when it was 55 MPH and the state police (DPS) would patrol that section like crazy. They might as well have been printing money, because it was brutal to drive/ride at 55 MPH in the middle of nowhere with nothing in site. Wayne |
Jlnance
| Posted on Wednesday, September 10, 2008 - 08:10 am: |
|
I think the general belief is the the engineers may have done it on purpose. Consider riding through a neighborhood with a speed limit of 25 mph, and you're going 25 mph. A kid runs out from behind a car and you run over him. Now consider the same thing except you're going 26 mph. You're in a hell of a lot more trouble in the second case. And if you can deflect some of that trouble by blaming it on the engineer who designed your speedometer, you're probably going to do it. The speedometer will read lower and lower, as you wear rubber off the tires. It will read lower or higher depending on how much air is in the tires. I'm sure that somewhere along the design path, someone made sure it didn't read less than the actual speed any conceivable tire pressure and wear level. Which means it will read low at other points. |
Lost_in_ohio
| Posted on Wednesday, September 10, 2008 - 09:59 am: |
|
Here ya go http://www.badweatherbikers.com/buell/messages/142 838/372257.html |
Neurorider
| Posted on Wednesday, September 10, 2008 - 10:48 am: |
|
Jlnance-I'm confused I guess (happens a lot) but wouldn't the speedo read higher as the tire wears? as in, smaller circumference so at a given velocity wheel turns more rpm so shows higher mph? or, speedo error would increase? I've noticed on big suv's the mpg looks better with worn tires and always thought that was for the same reason (truck really hasn't rolled as far as it's odo is telling it). thanks Richard |
Jlnance
| Posted on Wednesday, September 10, 2008 - 01:17 pm: |
|
Neuro - Yes, I have it backwards. |
Hoon
| Posted on Thursday, September 11, 2008 - 09:08 am: |
|
Paul56, 'Twatnav' is derogatory slang for Satnav. I find it can be useful in towns when you get very close to your destination if you're on your own and aren't able to read a map while concentrating on the road. I never really wanted one but my girlfriend (quite rightly in reality) thought it was best to buy me one rather than us having blazing rows in the car over map reading every time we went somewhere we didn't know. Ok,so the lady was right. I don't know what your satnavs are like but over here in the UK they can lead you on a merry dance if you follow their every instruction to the letter (might be due to the ancient nature of the roads I don't know). So I guess they can be a necessary evil but they can also be a PITA so a lot of people deride them. It's also 'less cool' to use them rather than 'being a real man' and using good old maps. |
Froggy
| Posted on Thursday, September 11, 2008 - 11:55 am: |
|
Hoon i think they go nuts sometimes everywhere. I have had mine try and take me down a road that didn't exist! My Dad has a cheapo no name unit, and his will literally drive him in a large circle rather than take him to his destination |