While riding over memorial day my 2002 FE 501 was making a louder than normal clanking valve sound, so I adjusted the valve clearances and it still made the sound. I rode it a bit more and all of a sudden the bike just died, no loud sounds just stopped running. I went to kick the bike over but had zero compression. Have'nt torn into the bike yet but was thinking that maybe one of the valve springs broke. Any ideas???