Inaccurate Speedometer = Inaccurate Odometer?

smhatahy · 11-02-2008, 05:55 PM

I have found found that the speedometer on my Honda Prelude is about 4-5% inaccurate. I was wondering if that would have any effect on the accuracy of my odometer reading?

What5647 · 11-02-2008, 06:55 PM

Yes it will.

doulos14 · 11-03-2008, 05:52 PM

Quote:

Originally Posted by Akshay

I have found found that the speedometer on my Honda Prelude is about 4-5% inaccurate. I was wondering if that would have any effect on the accuracy of my odometer reading?

that would be the problem....
jk

Anyways because the speedometer AND odometer measure miles (per hour or total traveled) by the wheel rotation if you see one as faulty then other will be also. You wouldn't by chance have different size wheels or tires? because bigger ones mean less miles(on odometer and speedo) and smaller ones mean more.

What5647 · 11-03-2008, 06:15 PM

Gear ratios make a difference as well, although I'm doubting that you've got aftermarket gears in that thing.

smhatahy · 11-03-2008, 06:35 PM

Everything is stock, so i'm assuming that Honda does this on purpose to avoid lawsuits from people that got speeding tickets or something? Or to reduce warranty time? Honestly though it's pretty lame because 5% of my odometer adds up to almost 7000 miles.

mulletman · 11-03-2008, 06:50 PM

Believe it or not, most speedometers are not that accurate. 4-5% isn't bad. With many motorcycles, you'll see upwards of 10% error. Thus, you get the guys with their 600-class sportbikes who make claims of 185... when the bike does no more than 160.

What5647 · 11-03-2008, 07:36 PM

Now you've got me wondering how accurate the speedometer is in my car.

Time to break out the GPS.

mulletman · 11-03-2008, 10:43 PM

Indeed. Just be sure to take into account the lag time of the GPS....

What5647 · 11-03-2008, 11:35 PM

I don't think that slight error would be enough to get me noticed by a cop...

Iceman-bass14 · 11-04-2008, 07:12 AM

Mine in my truck is totally screwed.Sometimes,normally in the cold, it will 'bounce' in a 15mph range(like from 40-55,50-65).

Folk_guy · 11-04-2008, 07:36 AM

What method did you use to determine that your speedometer is off? Could it be that the problem isn't your speedometer but your method of measurement? 4 to 5 % isn't that big a deal. Normally if you are within 10 miles per hour of the posted speed you won't get a ticket (there is always, the exception though). Non-stock tire sizes are the most common reason for speedometers to be off. Check the tire size against the sticker found in the door frame of the drivers side door.

**redbaron** · 11-04-2008, 02:08 PM

4% at 60mph is only +/- 2.4mph which is basically irrelevant. Yes, over a 600 mile trip you may see that you're off by 24 miles, but that's fairly minimal. You can always check with GPS.

Most speedometers that are off read high (typically) and i wouldn't start trying to drive faster than they indicate without absolutely confirming the exact speed. Mile marker check zones (not just mile markers) and GPS are the only way I'd really consider to be real reliable.

also, if you think your bike is off by 12% and you don't check and just ride that way, and then find out it's off by less than 1/10 of a mile after 10 miles, you'll feel pretty silly.

nate95366 · 11-05-2008, 08:51 PM

When I owned a 1990 Chevy Lumina as a college student, the speedometer worked well enough. The odometer, however, seemingly had a mind of its own. In the summer, it behaved as other normal odometers do, but in the winter it would move in reverse (not with the car in reverse, it would literally start rolling off miles) for about the first 10 miles of any trip before it would slow to a stop and then start counting forward.
For a while, I had a job that was 4 miles away from home and, being a student, I really only drove to work and back (walked to class). During that time, I put about negative 500 miles on my car. When it was finally towed to the yard two years ago, it had 235,000 on the odometer, but I'm really not sure at all how many miles the car actually traveled. I got it when the odometer read 161,000.

Nate

smhatahy · 11-06-2008, 12:18 AM

Quote:

Originally Posted by nate95366

When I owned a 1990 Chevy Lumina as a college student, the speedometer worked well enough. The odometer, however, seemingly had a mind of its own. In the summer, it behaved as other normal odometers do, but in the winter it would move in reverse (not with the car in reverse, it would literally start rolling off miles) for about the first 10 miles of any trip before it would slow to a stop and then start counting forward.
For a while, I had a job that was 4 miles away from home and, being a student, I really only drove to work and back (walked to class). During that time, I put about negative 500 miles on my car. When it was finally towed to the yard two years ago, it had 235,000 on the odometer, but I'm really not sure at all how many miles the car actually traveled. I got it when the odometer read 161,000.

Nate

That's actually and advantageous feature

Good ole American cars :-D