OR NOT. I though that the lock washer (see below) had solved the problem. Well, it worked for about a week, but now the wheel is back to rubbing again. I have purchased an Ultegra internal cam type QR skewer to replace the weaker external cam QR skewer that came with the wheel. Hopefully this will have enough pressure to keep the wheel in the dropout.
PROBLEM SOLVED! I got a 3/8 inch stainless lock washer (Everbilt Part #597 618 package of 2 for 60 cents) at Home Depot. I put one lock washer on the drive side of the rear wheel skewer. I positioned the lock washer on the skewer between the outside clamp/nut and the spring so that when the wheel is mounted the lock washer is between the frame and the outside clamp/nut on the outside of the frame.
Apparently, the slipping can result when the ridges in the dropout get worn off or clogged with something like paint when you do a rattlecan paint job.
UPDATE: OR NOT. I though that the lock washer had solved the problem. Well, it worked for about a week, but now the wheel is back to rubbing again. I have purchased an Ultegra internal cam type QR skewer to replace the weaker external cam QR skewer that came with the wheel. Hopefully this will have enough pressure to keep the wheel in the dropout.
