Originally Posted by *new*guy
that kinda sounds like the chainring is either distorting under pressure, bent, or you've got loose chainring bolts that are letting it move around under load.
But I don't hear any noise at all coming from the chainring area. Whether I'm riding, or have my bike stationary and upside down cranking it, the noise always seems to be coming from the cog area. I think the chainring's okay. I suppose the cog could "flex" under pressure, as well, right? But what still gets me is why it's so darn quiet when I'm "coasting" or backpedaling when I'm on the bike, yet a little noisy when I just have it upside down and am turning the crank either forward, or backward.
Ryan