I have resolved an issue with the digital version of microTach's produced before July 2009. The issue occurs on Harley bikes model 2007 or later.
Harley changed the coding on the digital bus signal in 2007. The result is that the microTach will operate normally in range 0-5000 rpm. At greater than 5000 rpm the microTach will only display the last reading of 5000 rpm, ignoring messages above 5000 rpm. (5500 on sportsters)
MicroTach's produced after July have resolved the issue and operate normally across the full range.
If you have the issue on your bike, I will replace the unit with an updated version. The simpliest method for replacement is for you to order a new digital version online at my website www.speedwayinstruments.com. Please indicate in the transaction or via email that this purchase is for replacement issue. I will ship out a new unit ASAP. Once you have the new unit; pull the old one off and replace with the new unit. Mail the old unit back to me and I will refund the full cost of the previously ordered unit. The old unit must be returned within 60 days of ordering the replacement unit in order for me to process the refund.
If you have any questions or issue please email me.
Thank you and sorry for the inconvenience.