I ride a 2001 520SX. Awesome bike that is well maintained. Since day one it has sounded very loud in the gearbox area. I have read many posts saying the same. The general consensus seems to be..Its a KTM thing, they all sound that way. Last month my gear box blew up! $1,000.00 to get it fixed. It still sounds like it is ready to blow up to me. I need to know...do all 520s make a louder gearbox noise than other brands of bikes? Has any one out there had any drive train problems with their RFS? I love my Power-Pumpkin but I am afraid that it may grenade again. Any input would be greatly appreciated.