Ouch. That is a new one. Wonder what someone did to that thing to make that happen. I've seen SVs get BEAT without anything like that happening. I had a gen 1 I picked up for short money that was timed wrong. I was sure you were going to find that here. They had set the rear timing without rotating the crank a full rev. The bike ran and idled okay and made some power near redline but fell on its face in the midrange and just felt weird. I brought it to a track day and had it up on stands. My buddy and I rode our tards in our session and debugged the mystery SV between. Couldn't figure it out. Weeks later I finally got it, re timed it and the bike ran like a top. Excellent compression and the transmission didn't even throw false neutrals. That day I learned that the SV (and many/most other twins) fire on both compression and exhaust strokes. My buddy said I had discovered a "big bang" SV.