Originally Posted by GTcommuter
I had a similar problem on an older Peugeot. M6 size holes, but un-threaded. I put M5 bolts with flat hex heads sticking out like Retro Grouch suggests and sandwiched them with washers. Then mounted the fender mounts to these and put a nut on the outside. It worked fine, but the fenders aren't weight bearing.
If it were only going to be fenders, I'd do that too. But it's racks and fenders
