Speedo correction on Interstate

[Gunner]

I know it is not a big deal, but that speedo being off was really bugging me.  I had previously corrected the speedo on my 750 Aero and just did the same to my Interstate.  I installed a SpeedoHealer with a universal harness.  The harness for my Aero was a plug and play, but they don't make one for the electronic speedo on the Interstate.  A couple of Posi-Locks and a couple of Posi-Taps to install the harness under the fairing and with a 6.9% correction programmed into the unit, the speedo is now dead accurate according to my GPS.

I also installed Memphis Shades Lowers today that work really well.  All that air coming over the tank is pretty much eliminated.  I wish I could have found the OEM lowers, but the Memphis Shades are pretty good for the price.

[N0tac0p]

pics showing the mounting?  pretty please

[OP2]

Also where yo got it and about how much they cost would be nice. This is the first I've heard of a unit that will correct the speedo.
Thanks,
Paul

[Gunner]

The SpeedoHealer will only work on the Interstate because the Interstate has the electronic speedo.  I purchased mine from the US distributor.  It can also be purchased on Ebay.  The universal harness is the one I purchased for the Interstate.

http://www.calsportbike.com/cgi-bin/store/index.cgi?back=&pid=1988&keywords=&product=Speedo_Healer&dept=Street-Track&count=1

I'll try to get a pic of the unit installed.

[Gunner]

And Healtech's site:

http://www.healtech-electronics.com/

[Andy]

What's the part number for the universal?

Never mind, I found it.

SHV4 + SH-U01

[Thrud]

If you calibrated your bike's speedo to the accuracy of your GPS then you've made a mistake.  GPS devices for consumer use are accurate to only a few meters of true GPS calculations.  For example, you can ascertain your GPS' accuracy in the menu of the Garmin Zumo 550.  My son-in-law works in the automotive division of Garmin (develops the Zumo line), and he told me that the 550 can be off as much as 75 feet at any point in time.  So, using your GPS to compare your bike's speed to GPS positioning will be inaccurate. 

[Thrud]

Also, you've not told us whether you're running with the OEM front tire size or something different.

[BonS]

If you calibrated your bike's speedo to the accuracy of your GPS then you've made a mistake.  GPS devices for consumer use are accurate to only a few meters of true GPS calculations.  For example, you can ascertain your GPS' accuracy in the menu of the Garmin Zumo 550.  My son-in-law works in the automotive division of Garmin (develops the Zumo line), and he told me that the 550 can be off as much as 75 feet at any point in time.  So, using your GPS to compare your bike's speed to GPS positioning will be inaccurate. 

Absolute accuracy is a different beast than repeatability and rate-of-change calculations which is what the speed calculations are all about. Yes, there's noise in the calculations that are an artifact of absolute position calculations but that averages out quickly and allows the speed calculations to be quite accurate when comparing to a DOT speedometer that's always calibrated to read high. Now, that said, it's quite a different thing if you're driving in small circles. Then the GPS absolute position calculations will screw up ground speed calculations.

[Thrud]

Huh?  I think what the original poster was stating was that he was comparing the speed of his speedo vs. the speed reported by his GPS.  I was stating, for example, that a consumer-grade GPS receiver, such as the Zumo will be inaccurate over a distance of several meters--all the time. 

For example, I recently returned from Sturgis and over the course of my travels I noted about a 5 MPH difference between the speedo on my Interstate vs. my Zumo 550.  Which is more accurate?  According to my Garmin engineer relative you should believe your bike's speedo, if you're running with OEM size tires. 

So, you cannot accurately compare the two results, whether driving in a straight line or in circles.

[PhredValk]

I wonder if this unit can alter the readout enough to make an MPH speedo read in KPH? I'll have to do some reading...
Fred.

[58Woody]

What's the part number for the universal?

Never mind, I found it.

SHV4 + SH-U01

I have the problem with the wind coming between the tank and the bottom of the fairing on my interstate. I see the pic of the lowers on the side of the radiator. Was that the cure?

[PhredValk]

Woody, search for lowers deflectors and bakers. Lots of remedies for that wind.
Fred.