Speedometer 5 MPH off!

[rog6785]

Does anyone know if there is a way to recalibrate the speedometer. I have a 1986 GL1200 Aspencade and the speedo has been off ever since I bought it. Comparing the speed to my phone I 5 off. When I am going 65 the speedo is saying 60. I replaced the back tire and thought that would help and made not difference. The odometer I have checked that over a five mile stretch with mile marker signs and was right on. So any suggestions? Not a big deal just kind of annoying if someone has a quick fix for this.

[Wilcoy02]

You just need to live with it. There is no fix for this.

[rog6785]

thanks that is what I thought.

[tamathumper]

Interesting, the GL1800 is off by 5 mph in the other direction, when the speedo says 65, you're only doing 60.

[AZgl1800]

my 1800 is off 6 mph 'fast' at 70 mph by the GPS reading.
I ignore it, been that way since I got it.

My truck speedo reads 3 mph slow, so 60 mph is 63 mph...
none of them are accurate.

[kwthom]

Until about 2009, that seemed to be a Honda design 'issue'; the odo and the speedo error couldn't be more closely synched.

There is no federal specifications for odometer error.

Shortly after that class action lawsuit came out over odometer errors, it was miraculously solved.

[hondapotamus]

My 1800 (2001) was off by about 5 and so I changed the rear tire to a 70 series rather than the 60 series that came stock (about 1" in diameter larger). That larger tire brought it right on spec as verified by my GPS. I don't know if that's an option for you to go to a different tire size.

[rog6785]

Thanks for the feedback I will check into that.

[Rolfsted]

I had an 86. I believe the speedometer is driven by a gear on the front rim.

[CrystalPistol]

Does anyone know if there is a way to recalibrate the speedometer. I have a 1986 GL1200 Aspencade and the speedo has been off ever since I bought it. Comparing the speed to my phone I 5 off. When I am going 65 the speedo is saying 60. I replaced the back tire and thought that would help and made not difference. The odometer I have checked that over a five mile stretch with mile marker signs and was right on. So any suggestions? Not a big deal just kind of annoying if someone has a quick fix for this.

Back tire has nothing to do with it on a 1200 as the speedometer is taken at front hub. My '85 Aspencade was just about exactly 10% off, reading 55 on the speedometer but 50 on the Kustom Signals Radar I set up on the bike (I attached an antenna pointing straight back on a bracket I fashioned to hold it on the rear rack, the readout was strapped to the faux tank top, I plugged it into an outlet … it was the unit that I was assigned for my job). Was the same at higher or lower speeds, like 44 on the speedometer caused the radar to read 40, 77 on the speedometer caused radar to read 70. I just used a label maker to make a chart.

I extrapolated the 99/90.
It was originally worse with the slightly shorter Dunlop Elite GT front tire, the Elite II was a hair taller and spun slower at speed. I know because my finger was a tight fit between the Elite II and front fender than it was with the Elite GT. The Elite II steered better too.
As I recall, the odometer was spot on over 10 miles on I-81 (10 miles with 1/10th mile markers too) with the Elite GT, but was short a percent with the Elie II. Seems one was a 130/90-16 but the other was a MR90-16.

Told me that Honda intended the error to keep customers licenses safe from unintended speeding tickets by providing a buffer. Bought it in 1995, was on a trip to Ohio for Vintage Days, buddy (my work Sgt.) on his HD said I was going too slow … so I checked when we got back. Sure enough, when I thought we were at the limit he was wondering why I was poking along.

Interestingly, my 1500 was off a hair, not as much, and the odometer was off about the same slight amount.

[Troyite]

Similar issue. Just did a 200 mile trip the Speedometer read 5 mile over what my GPS showed- Went past a few "radar" signs they agreed with my GPS - will changing the front tire on the Aspencade help?
Is there another fix? or just know I am traveling 5 mph than the reading? and live with it

Thanks for your responses

[Rambozo]

If you can still find one, a good speedometer shop can recalibrate your speedometer.

[LeMaitre]

If the pickup is on the front wheel, as it is on the 85 GL1200A. The easiest way is to change the front tire to one with a larger diameter.

-Mark