Curtlo chainstay rescue
A regular client of ours sent us a message from the trail one day this past fall bemoaning that his beloved custom Curtlo had broken. It wasn’t made custom for him, as he was the second owner, but it was his favorite bike by a long stretch. That’s saying a lot because he has all sorts of exotic and custom steeds in his stable! A Curtlo is a pretty modest bike relative to some of the other things he has brought by the shop over the last couple of years.
Upon inspection, the damage was pretty obviously because moisture had accumulated at the back of the chainstay and allowed the tube to corrode right around the high stress point of the dropout tang. The bike had expansion/drainage holes in the back of the stay, but even so, this frame had enough exposure to allow moisture to do a number on it from the inside out. The stay wasn’t too rotted, so we decided the best fix was to clean the inside of the existing stay, remove the broken pieces from the dropout tang, and rebuild from there.
The course of action was to clean up the dropout after removing the broken end pieces of stay, and then key in a stainless post that would insert about 25mm into the existing stay. This is a tricky thing to do because if alignment is off by 1mm at the dropout, it could easily manifest as 7-9mm at the tire. Everything has to be just so with rear end alignment or stuff gets messy and ugly at the actually rolling point of the wheel.
Since we were keying in a post that was a couple millimeters smaller in diameter than the O.D. of the chainstay, the plan was to build up a fillet and then shape the tube to match the drive side stay as best as possible so the repair wouldn’t really be very noticeable unless it was specifically called out to someone.
All in all, things didn’t shape up to be 100% exactly symmetrical, but so close that few people would be able to notice anything was different unless told otherwise under a close inspection. Thankfully Doug Curtis’s frames are often powdercoated with basic solids so blending a paint match wasn’t too tough for the casual observer!
