I want to do a sscx race on my geared cross bike. I pulled the cassette and put on a chris king cog and spacers. chainline is perfect. Since I don't want to mess with my geared bike more than I need to, I'm leaving the shifters, cables and derailleurs on the bike, just pulling off one chainring.
When I got it all set up and test rode it, the chain skips under heavy load. It doesn't skip on the cassette. The chain has less than .75 stretch checked with a chain stretch gauge. The king cog is nearly brand new, and the teeth are much taller than the teeth on the cassette. I also adjusted to barrel so the top pulley is directly below the cog.
Anyone have any ideas as to why it's doing this, or what I can do to fix it?