On Sun, 13 Feb 2011 18:59:18 -0800, Pilgrim
wrote:

Is the purpose of the goop they slather around the bead of a tubeless
tire to lubricate during installation, to help seal the tire rim
interface, or both? I have a freebee dolly on which one of the tire has
a very very slow leak at the interface. What is this goop? The local
auto parts store was of no help.

Generally, it's just a soapy water mix for lubing the tire onto the
rim. Once it evaporates, it's gone. There is no extra sealing
capability.

To seal from the inside, install some of the green slime.
http://tinyurl.com/4nz5zz2

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