I have a 99 ZR 600 EFI. I have replaced 2 front driveshafts in the last two weeks. The last one broke last night. I was riding on the grommed trail. I did run over a stump that was even with the trail. I was doing about 30 mph. All I felt was a thump, I have heard the same noise often driving through powder or a frozen section of bog. Wondering if there has been any problems that anyone has heard of or were conditions just right enough for it to fracture. The one I replaced last week, stems from a similar incident, but appeared to have been broken for a while. The last one failed inside one of the drive wheels. Last night it broke directly in the center of the shaft.