So I had a harescramble last weekend and ended up starting 2.5 min behind my class because of a starting problem with my 2005 CR250. It was starting great all morning and then on the starting line after the national anthem I kicked it over, it ran for about 10 seconds and then died. After it died the engine felt like it had no compression, there was virtually no resistance in the kickstarter (it was easier to kick than a 125). At this point I thought my race was done. After 2 minutes of kicking someone push started me and the bike started right up. After I got going I was able to restart the bike fine if it stalled and after the race everything felt totally normal including the compression. It was a very hot day around 90+ degrees. Does anybody have any idea what could've caused this problem? Everything seems fine now but I want to get this sorted out before my next race. Oh and the topend was rebuilt about a month ago so I doubt that's the issue.