Hi all, first post. Well my thumb found the space between the chain and ring this evening on the fixer I'm building. It was just the very tip, didn't even get any nail so my thumb popped right out with with two nice bite marks. I've read plenty about this very danger with fixers and still managed this close-call within about a minute of having the chain on. Scared the crap out of me, I guess that's a good thing. So, just thought I'd wish you all safe maintenance and happy cycling.