Ok so this still isn't sorted. I swapped for the 12kg servo. still the same symptoms. I have changed my radio gear to 40mhz, still the same.It just seems as though this servo won't work with my excelorin.....but I know it does as someone else has the same speedo/servo combo. Does anyone out there have any idea as to what I can do? Other than to sell it all and take up knitting.........