Author Topic: Changing Rollback Odometer Mileage Data on Electronic Motorcycle Speedometers  (Read 4124 times)


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It is possible to rollback the odometer on Harley Davidson electronic speedometers, but it requires special tools to access odometer data on EEPROM memory chips, and some speedometers on other vehicles store the information on micro-controllers. I was never interested in changing the odometer, but I did want to find a method for unlocking the speedometer, so the speedometer can be used on another motorcycle.

Some tools that will work to change odometer data on electronic speedometers are the Tacho Pro, USA Prog and DSPIII+. All these tools are manufactured in China. The Tacho Pro is the least expensive, but the software is no longer supported and you can't get updates for the tool, and I have heard several people online complain about the tool not working for some applications and destroying the speedometer, so be careful with this tool (I am not positive the TachPro will even work on HD Speedometers, so be careful with this one). The reason the Tacho Pro is so cheap is because the software is old and you can no longer get updates, and the instructions included with the tool are poorly written and difficult to understand. The USA Prog and DSPIII+ is up to date and more reliable than the Tacho Pro, but they are very expensive. The cheapest package for the USA Prog is $500 and the accessories you will need are extremely expensive, so look to spend a minimum of $1000 on this tool. The most expensive version of the USA Prog is around $5300 and it is called the Full Version. Same story with with the DSPIII+. Its very expensive!

There is a program called TachoSoft Mileage Calculator that will run on your PC. The program will take your mileage and encode it and display the hexadecimal value, tell you what type of EEPROM chip your speedometer uses, and where the odometer data is stored on the EEPROM chip. All the EEPROM chips I have seen used on Harley Davidson electronic speedometers use a 93CXX chip. With the information given to you by the TachoSoft software you can basically use any EEPROM programmer with the proper zif socket to change the memory contents and write the information to the EEPROM chip. The Tachsoft program will provide you with the encoded odometer information, and where it is stored on the EEPROM chip, and with the programmer you can read the contents of the EEPROM chip, make changes, than write the information back to the chip. This is the cheapest solution I have found for changing speedometer information. Its possible to make your own programmer, but programmers are only around $100, and you can buy programmers that plug into your PC's USB port. In my opinion this is cheaper and much more convenient than trying to build your own programmer. A good USB programmer is called GQ-4X
« Last Edit: November 09, 2014, 07:46:50 PM by smallengineshop »
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