1. How do I increase the number of km’s on the speedo without actually riding it or putting it up on stands and running it?

2. Is it possible to put an old speedo on from another fatboy with higher kms and power it up for a few seconds, without starting the bike or engaging gear?

I have been told that 1 above is not possible, and that 2 will immediately produce a “VIN Err” code?

Thanks in advance. 

Both the ECM and speedometer retain the odometer value. If the speedometer is replaced, it displays the odometer value stored in the ECM. The replacement speedometer will become locked to the ECM after 50 km (31.1 mi) have been accumulated. The trip B odometer displays the countdown mileage. Once the countdown reaches zero, the speedometer is locked to the ECM. If installed on another vehicle the odometer displays "VIN ERR". If the speedometer is removed from the vehicle before the countdown reaches zero, it has not been locked to the ECM. This mileage countdown allows for a road test to verify that speedometer replacement was the proper repair.

During the 50 km (31.1 mi) countdown period (before the speedometer is locked to the ECM), the security light flashes for up to 15 seconds when battery power is restored to the electrical system, while the new gauge synchronizes to the ECM.

When I replace the speedo on my 08 Fatboy I had the speedo set to the current millage the old speedo displayed. 

Many of you have correctly said what happens when you install a new speedo, but I can’t find any real data about installing an old one, other than at some stage the old speedo will show “VINerr” indicating that the old speedo is married to a different VIN number. I just don’t know when that occurs after power on, is it immediate, does it take some time, do you have to ride it, or….

As to why the hell I would want to do this, I unfortunately can’t say, however your comments and experiences are most welcome.

My bike is a 1HD dyna that I imported from the US. I went through American Vehicle Imports in Traralgon to get it complied.

The speedo was tweaked so that the odometer read in kph rather than mph.

The guy I dealt with there was John. I thought he was a senior technician but he may have been the owner, John Bakker.

I'm sure he could answer your question if you give him a ring.

I have had several 1HD imports prepared for "compliancing" here in Perth WA. A few years back now as that market has died right off due to exchange rate etc etc.

Anyhow, I used the SAME original "Aussie from new" 2008 Softail Custom tank mount speedo to get several bikes passed.

Each bike showed the K's from the original Softail (66,000 from memory) as all were lower K's than that stored in the ECM.

Not all the bikes were 2008 , from memory the speedo covered 4 model years and quite a few different models not only Softails.

Some of the guys immediately put their MPH speedos back in (THEY did it officer NOT ME haha..)

Others bought the combined Km/H speedo/revcounter units new after compliancing , and they showed the original Miles to K's converted numbers.

That's my takes and hazy memories. I still have that 66,000 K's 2008 Speedo in the shed to this day