Author Topic: Is your speedometer telling you the right MPH?  (Read 18648 times)

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Offline Really?

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Is your speedometer telling you the right MPH?
« Reply #25 on: August 20, 2011, 09:09:52 am »
No wonder I don't get tickets anymore.
I don't have a motorcycle, sold it ('85 Yamaha Venture Royale).  Haven't had a CB750 for over 40 years.

The Wife's Bike - 750K5
The Kid's Bike - 750K3

Offline vance

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Re: Is your speedometer telling you the right MPH?
« Reply #26 on: August 20, 2011, 09:14:10 am »
If you happen to have your gauges apart you can pop the needle off and move it the direction you need  to make the reading more accurate
1977 cb550k "Old Gray Baby"

Offline The Laughing Man

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Re: Is your speedometer telling you the right MPH?
« Reply #27 on: October 28, 2012, 07:43:57 am »
Well it's reassuring to know when I ride the older bikes I'm naturally inclined not to speed. Still doesn't surprise me. There are numerous rumors that some auto manufacturers made their speedometers five to ten MPH faster on purpose to cut insurance costs.

Offline CycleRanger

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Re: Is your speedometer telling you the right MPH?
« Reply #28 on: October 28, 2012, 07:53:30 am »
Well it's reassuring to know when I ride the older bikes I'm naturally inclined not to speed. Still doesn't surprise me. There are numerous rumors that some auto manufacturers made their speedometers five to ten MPH faster on purpose to cut insurance costs.
Changing tire size on a car will alter the speedo reading slightly.

The speedo on my K5 reads about ~15mph too fast. I have to ride at ~75 just to keep up with traffic! ::)
Do you have a copy of the Honda Shop Manual for your bike? Get one here:
https://www.honda4fun.com/materiale/documentazione-tecnica
CB750K5        '79 XL250s     CL350K3
CB750K3        '76 XS650      '76 CJ360T

Offline LesterPiglet

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Re: Is your speedometer telling you the right MPH?
« Reply #29 on: October 28, 2012, 09:45:57 am »
Changing the profile of the front tyre/diameter of wheel will alter the speedo reading.
'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Draw and drawer. Could care less/couldn't care less. Bought/brought FFS.


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Offline BobbyR

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Re: Is your speedometer telling you the right MPH?
« Reply #30 on: October 28, 2012, 10:26:54 am »
So those that think they have done the ton ;D ;D ;D ;D ;D ;D
Dedicated to Sgt. Howard Bruckner 1950 - 1969. KIA LONG KHANH.

But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?

Offline Bob Wessner

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Re: Is your speedometer telling you the right MPH?
« Reply #31 on: October 28, 2012, 01:20:48 pm »
Ha, good point. Perhaps it needs to be a "GPS certified" ton.  ;)

I suspect a ticket from the local constabulary would do also.  ;D
We'll all be someone else's PO some day.

Offline BobbyR

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Re: Is your speedometer telling you the right MPH?
« Reply #32 on: October 28, 2012, 01:59:58 pm »
Well maybe call it a metric ton. ;D ;D ;D ;D ;D
Dedicated to Sgt. Howard Bruckner 1950 - 1969. KIA LONG KHANH.

But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?

Offline The Laughing Man

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Re: Is your speedometer telling you the right MPH?
« Reply #33 on: October 28, 2012, 02:45:05 pm »
I've found that my 750 is off by about 2 mph (low per the speedo) against a GPS. Similarly, my Honda CRV is off by about the same amount per the GPS. One can almost think this is deliberate for liability reasons.  ;)

Bingo