I tried unsuccessfully to patch a very small hole in the tread of a slick. I'm thinking it still leaks because there is just not much rubber for the patch to bond to once I buffed off the ridges. Has anyone successfully plugged one? If so what type of plug did you use? I have always had success with the brown rope type plugs on normal passenger car tires

When we ran bias ply slicks, we used the rope type plugs. Not sure if I would try it on a radial slick but haven't run into that situation yet.

Has anyone done it on a radial slick?

2BKING

Wouldn't it be the same as a radial tire on a car or truck?

Rope plug lasted a long time in a bias slick tread

^^^^^ Agreed! I’ve rope plugged (passenger brown type) several rear bias slicks and even a lightweight racing bias front tire in the staging lanes with success.

Same as the other guys, I once used a rope style plug, and it was still leaking slightly.
One good burnout and it sealed after that.
Slick was about done anyway, but it got me through that one race, one TT plus 5 or 6 rounds.

I've done both radial and bias punctures with the gooey black twizzler looking rope style kit.
No issues. Run tire to end of service life.