90% chance its the clutch plate that explodes! I had the same issue on the Sporty and the ring was 50% disintegrated - lucky no damage to the internals. Its a VERY common thing.
hi Folks, My FXST has 35,000 km of fairly sedate mileage. I've had it since 5000 km and it seems to need clutch cable adjustment more often than I expect. My Sporty and other bikes I've had almost never need clutch adjustment. I've also done a check on the adjustment at the pushrod behind the derby cover and that was within spec. If I use the clutch a lot in traffic, the clutch lever rapidly gets more play than the spec in the service manual. If I put up with the extra play, I can probably make it last between oil changes without doing any adjustment. If I tried to keep the lever play within spec all the time it would need adjustment every second ride. I don't do burnouts and I don't feel like I ride it hard at all.
My 2011 fxst with just about 60,000km has only needed clutch adjustment a couple times.