I noticed some odd noises near my front bottom bracket, and discovered that my front timing chainring is coming loose from the crank.
What has been happening, is that the chain ring bolts have actually been grinding away radially, so the bolts no longer fit snugly in the holes. Now that they have gotten loose, they are probably chewing up the holes in the crank arm and the chainring as they move on every rotation of the pedals. (I can't confirm how much/little the crankarm/chainring holes have gotten chewed up, since, the bolts/nuts have been so mangled that they are frozen and can't be tightened or loosened. FWIW, the crank arm/chain ring are about 800 miles old.
I'd like to get this fixed ASAP, but am not sure what all to do:
1) I'm guessing I'll have to drill out the old bolts, carefully, and replace them, unless anyone knows a better way to apply enough torque to them to get them to move. They are the style where the bolt uses 5mm hex and the female uses a large flat screw driver to get started, but the bolt tightens into the screw drive channel, so to loosen them, all I've got is a 2mm-ish slot on either side of the nut to prevent the nut from turning.
2) I've got new bolts on order, but I'm nervous about what I should be replacing. If I'm lucky, the crankarm and chainring won't need replacing, and new bolts will do it. BUT, if the assembly still wiggles when I install the new bolts, is there some step I can take to secure things other than replacing the crankarm and the chainring?
3) Is there any way to use digital calipers to measure the holes in the crankarm/chainring to reach a better decision on whether or not to replace them? IOW, if the holes are supposed to be 16mm, but have grown to 16.05mm, what is the line where I should replace them? (I just made up the numbers for that example)
4) Is this a random thing or could I have done something stupid to cause this? I was the one who installed the new parts 800 miles ago. Anything I should do this time to prevent this from happening again?