In the last few months I have tried two of the available speedometer re-calibrators and neither one was able to get the job done without another problem occurring. I tried the Dakota Digital one first. This unit was easy to use after the wiring was installed. It had two buttons on it for easy adjustment while moving. I wired it up and left off one of the bags and headed down the road. I had my GPS turned on and I was able to calibrate the bike perfectly. Speed as well as milage were right on the money. I have a 7% deviation. After the calibration I noticed the 6th gear indicator and the cruise didn't work. I thought maybe I had blown a fuse but after checking found out I hadn't. I called Dakota Digital and I was told to back off from my calibration and all would work again. I tried that and yes all worked again but now I was out of calibration. They could offer nothing in the way of tech support except to say that I could only calibrate it to what the original error was. In other words if my bike had a 7% deviation all I could calibrate out was 2% because Harley's spec is 3-5%. It went back. Next I tried Yellow Box. They're unit had dip switches on the out side and a chart to help with setting of the switches based on your amount of deviation. I looked on the chart for a 7% deviation and moved the dip switches accordingly. The speed and odometer were right on the money to my GPS. It was uncanny how accurate it was. The only problem was the same thing happened. Yellow box tech support was at least much more helpful with trying to determine why it wouldn't work as they and I had hoped. They had me send them all of the schematics. We exchanged many emails back and forth before the decision was made to send it back for a refund. All in all I was disappointed and still do not have a less expensive fix for the re-calibration issue other than a TTS master-tune module that allows for speedo calibration (already have a SERT) or going to Dakota Digital Gages which allow for the same thing. Any of you contemplating re-calibration it seems like on the 6 speed bikes none of the after market re-calibrators will work as advertised unless your willing to accept the 6th gear light not working and if you have cruise having that not work either. If anyone has a fix for this I'd really like to know.

 

I recently upgraded my SERT to the TTS MasterTune for $100. The first thing I did was calibrate the speedometer. It now reads exactly the same as my GPS. That alone was worth the upgrade price and my 6 speed light works just fine.

 

I ran the S&S calibration box for several years and had no problems. It plugs in line with the speedo sensor.

 

There is another brand available called a Speedo-Healer. I had one one my previous bike (not a HD) after I had issues with the Dakota unit (cruise kept kicking out).

You program the percent correction into the unit while the bike is stationary by pushing buttons until the unit displays your correction factor, such as -6.9% or whatever you need.

It worked fine on that bike but I cannot attest to how it would work on yours. Might be worth considering if you can find a supplier.

 

I've also heard the speed-o-healer works very well. Guys on the VTX forum used it and were happy. I just look at my GPS to get accurate speed.

 

Speedo Healer will fix the the speedometer error but the 6th gear indicator and the cruise wont work.

 

Any of these units appear to work with the five speed transmissions. They all work with some draw back. If you don't care if your 6th gear indicator light works your good to go on the 6 speeds. I can't concieve that having the cruise not work would be okay though. Like I said they work with some draw back on the newer bikes.

 

I could deal with the 6th Speed light not working, but not the cruise control...

 

I just live with it and watch my GPS if I really need an accurate speed.

The 08 SG reads 5 MPH fast at 70 MPH and the new 2010 Ultra reads 3 MPH fast at 70 MPH.

 

My 08 read 73 when my GPS read 70
My 09 read 73 when my GPS read 70

On my 09 I changed out my rear wheel to a 17 x 6 with a 200/55VR Avon Cobra
and now my speedo is exactly the same as my GPS at 70.

I know that probaly doesn't help you, but it's all I got. Sorry.

FYI my GPS is dead on with mine and my wife's cars at 70.