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Speedo is off.

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Old Jul 23, 2009 | 09:49 PM
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Default Speedo is off.

My speedo is off by 6 mph slower. I thought that the tires maybe the wrong size, but they are the 225/70 15's which are the right size. Any clues on how to problem solve this one?

Thanks again. This sight has been awesome.
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Old Jul 23, 2009 | 10:34 PM
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If it is always off 6 MPH, regardless of your speed, move the needle.

If it is off by a varying amount, depending on your speed, your rear end may have been changed and you will need a new speedo gear.
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Old Jul 23, 2009 | 10:37 PM
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Mine was off and it had the wrong spedo gear in the tranny.
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Old Jul 24, 2009 | 08:28 PM
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The gears are changed to correct the ODOMETER. The HEAD is then calibrated to the corrected cable speed.
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Old Jul 24, 2009 | 08:50 PM
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If the speedometer is off 6 Mph, you subtract one tooth on the gear in the transmission. As a general rule of thumb 5 mph = 1 tooth!

Willcox Inc.
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Old Jul 24, 2009 | 09:11 PM
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Want the cheep but effective way....buy some stickers and put on the face.....these speedos are NOT LINEAR.....for instance, mine is dead accuate with Garmin up to 70mph.....80 indicated is really only 78 mph.....

100 indicated is only 94......get my drift???

my tach is 300 rpm high at 3000 rpm reads 3300....now that dont change as even at 6000 rpm it reads 6300....go figger...

but at 1500 it's dead nutz on....

makes me want to go dig it allllll/////


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Old Jul 25, 2009 | 02:25 PM
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Originally Posted by Willcox Corvette
If the speedometer is off 6 Mph, you subtract one tooth on the gear in the transmission. As a general rule of thumb 5 mph = 1 tooth!

Willcox Inc.
Yes. And it is not an expensive fix.
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