Stripped Chainring Bolt (Help)
 

Well, it finally happened. I went to change my inner chainring on the campy cranks and what do you know? The one chainring bolt is stripped and I am unable to loosen the bolt. Does anyone have any suggestions about getting this bolt loose?

thanks
howard

Depends how bad it is. You could just keep the pressure on the edge that grips best, but I guess you've already tried that.

The only thing I can think of is to try and jam something into the allen head so that it can't move and then use that to loosen it off. You got any punches that could trap on the metal? If so, do that then use a pair of plyers to twist the bolt out.

Any chance of drilling it out VERY carefully?

Try a brand new 5mm allan wrench. i expect your problems came from using a worn wrench that had the sharp corners rounded a bit from use and it didn't get a good purchase the first time.

If that fails, and it probably will at this point, you could drill out the bolt using a drill bit just slightly smaller than the hole in the chain ring then chisel off the head which will be held by a very thin ring of metal. Another possibility is to cut a slot across the bolt head with a fine tooth hacksaw and try a large screwdriver to turn out the bolt.

1/4 " drill bit, right through it,

hi matt,

what I am going to try is to get a larger screw and screw a larger bolt into the stripped bolt and then try to get something moving, thanks for your help i'll tell you how it works out

I'm not quite sure what you're proposing there, grall1126, I'll be honest.

I guess it's a variation on my theme of jamming a punch in there and giving it a twist.

But whatever, good luck. I hate stripped threads with a passion. They're just so needless and so time-consuming. Do keep us informed.

hi matt,

well, i tried all solotions and i know they make a bit that is threaded the oppositie way and I am going to see if I have one at work, i tried the screw method didnt work and i didnt want to drill it yet since then i will need a bolt and i dont have an extra one so i can ride, been riding with large chainring now avoiding the hills, thanks
howard

Any LBS will have chainring bolts to replace your damaged one. They don't have to be specifically Campy.

When I'm dealing with stripped heads or slots, sometimes it helps to put a little valve grinding compound on the tool. The grit seems to help keep the tool from spinning.

seres,

good idea i never thought of that but I have a screw extracor from work and I am going to try that, also thank you everyone for the tips I greatly appreciate it. By the way does anyone know where I can pick up a old shimano rear wheel 6-7 speed?