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Speedometer, odometer, mpg accuracy w larger tires

1285 Views 12 Replies 9 Participants Last post by  socalschlegels
Recently, outfitted my '20 Elite w Nitto Nomad Grapplers 265 50 20 and realized all data has mpg etc can't be calibrated to new tire size. My tires are 1" taller. Does anyone have a calculator to adjust these readings to accurate?
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Tire Wheel Vehicle Car Automotive side marker light
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The vehicle settings cannot be modified to the new tires size but you can use this site 馃憞 to give yourself an idea of how much off your readings are.
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There is a company called HealTech Electronics, and they make a device called "SpeeoHealer" for Non-mechanical MOTORCYCLE speedometers. I have installed on on the last several bike I have owned. What it does is; you calculate the speed difference shown on your dash VS your GPS. You input this into their on-line calculator which give you an adjustment % to input into the installed device. It works extremely well.... at all speeds. (You notice the error more the faster you go). It is a very common issue for motorcycles as even the smallest tire sized change can have drastic speedo/odo error. Also, sprocket size changes on chain drive bikes create wild speedo/odo errors. All that being said This particular company & item is for motorcycles only.... But you might want to contact them to see if they can recommend one made for an automobile. Just a thought..... Good luck.

HealTech Main Page - HealTech Electronics - Smart Tech for your Ride!
SpeedoHealer item I mentioned - SpeedoHealer v4 (SH) - HealTech Electronics Ltd.

P.S. - Be sure to consider any warranty issues if you choose to try this.
I don't think this has a Passport compatible connection harness, even if you manage to connect it you might end up with the Passport throwing a million error messages considering how sensitive its electronics system is. A mental note of the percentage of error you are dealing with while driving is the only way to go.
Besides, at resell time, depending on the ODO error direction, it may work out to his advantage LOL.
馃槅 馃槅
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