Thanks for the heads up, Tim B.

I didn't have problems sealing the Panaracers to my Mavic 221's. I was surprised how easy it was.

I went out on a real mild ride and didn't have any problems---no loss of air.

Then I took the wheels off and banged them as hard as I could against the sidewalk curb and still no issues.

We'll see more when I go out to Noble Canyon or Mission Trails here in San Diego next week. I'm going to bring two tubes just in case.