Rim locks

[thumperhead]

Im having trouble keeping my rear tyre firm on the rim, It creeps around making the valve stem lean over.
I only have this trouble when I use less then 15 psi, But 15 psi is too much pressure and makes the rear tyre bounce around too much.
Im thinking about using "rim locks" in the rear only. 14 inch wheel.
What are people using to fix this problem.

 

[xLOCOx]

Go the rim lock, I'm running front and rear rim locks, i used a pedestal drill to drill my holes for the rim locks,
I think I went with the quarter way round method from the valve stem, good investment for a couple of bucks to save ripping out the stem!