Speedo Error, Adjustments other than tire size? |
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Speedo Error, Adjustments other than tire size? |
Van B |
Oct 28 2021, 07:20 PM
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#1
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Senior Member Group: Members Posts: 1,616 Joined: 20-October 21 From: Maryland Member No.: 26,011 Region Association: None |
So, compared to GPS, my Speedo is consistently 5mph too optimistic. My tires are 195/65-15. I’ve read in other threads that has shown to be a good size for correcting error.
So, not really wanting to go taller still, is there any other way to calibrate the Speedo? Thanks, Van |
ClayPerrine |
Oct 29 2021, 05:59 AM
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#2
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Life's been good to me so far..... Group: Admin Posts: 15,820 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille |
The reason your speedometer is off is because the drive cable is spinning faster due to the smaller tires.
To correct this, you can open the speedometer up and adjust the spring tension on the needle to correct the calibration. I don't think any of us have a speedo calibration bench, so you will have to get some help to do it. Have someone drive using a GPS speedometer app on their phone while you sit in the passenger seat and adjust the spring tension. Do that until the speedo matches as closely as possible to the GPS speedo readings. You will want to compare at different speeds to make sure it is as accurate as possible. Or... You could put in a GPS driven speedometer. GPS Speedometer Thread I have been running the GPS speedo for 7 years now and it has always been accurate and reliable. Clay |
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