Tony, the front tire was replaced about 1 year ago and approximately 8,000 miles. He did use a breaker bar on axle shaft. For some reason, he didn't have a wrench on the nut while cracking on the axle shaft from the left side (facing the bike). He did mention that the axle clamp bolt was loose on the right side. Umm....thought they should both be loose prior to removing the nut from the shaft. Anyway, we inspected the axle and didn't discover any damage...i.e. scuff or corrosion.
No observable damage to the gear drive/notches. No damage observe on the instrument panel where the cable attaches. Replaced the speedo housing along with the cable (dealer expense) and checkout ride was good. Speed indicator spot on with GPS MPH (upto 115+), however the odometer mileage has a slight variance from what is reflected on the GPS.
Still can't understand how this happen or why he didn't remove the cable from the housing prior to attempting to loosen the axle nut. Lucked out this time....amazed that the speedo gear drive didn't get damaged.
Always appreciate everyone's thoughts/comments!