Speedometer Accuracy...
#12
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My speedo indicated 70 when I was actually doing 66-67 according to my GPS. (This was pretty good compared to my Gold Wing that indicated 70 when I was going 63-64!) I used the TTS to tweak it. Now it's just *barely* optimistic so I'm going 68-69 at indicated 70.
#13
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Exactly. My speedo is 3 mph faster than my GPS. I've been intending to ask a buddy, who is a local LEO, check me on his radar. But I seem to always have something more important to do.
#14
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Mine shows 2 - 3 MPH faster than the GPS and it seems to me that most or all are that way. My theory is that HD designs speedos purposefully with a 'fudge' factor on the high side to account for slightly different tire sizes and other variables. If the speedos were off on the low side it could be cause for a DOT recall.
I have no facts to support this idea - just a guess.
I have no facts to support this idea - just a guess.
#19
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I use a GPS to measure all of our vehicles speedos. My Kawasaki is WAY off at highway speeds, close to 10 MPH. The Harley is dead on. I do not take the sport bike out for long highway rides anyway so I have not messed with it.
#20
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I don't think comparing to GPS is the correct way to determine if the spedo is off. A calibrating facility is the only correct way to check accuracy. Both my GPS (garmin and tom tom) read different and are different than the spedo. Unless you have a military GPS, they are probably off some also. GPS owners manual states a +/- factor for mine.