rquintero said:I was talking about one of those really dumb caps, where if the PSI is > x then it shows a green "dot", and below that the little plastic thing inside flips and settles to the red dot. Cute, and surely a limited benefit, but worth it for a couple of bucks a piece.
Don't waste your money. They don't work at all. I had a set on one of my bikes and the indicator didn't change even with an 8lb change in pressure. (25% pressure loss)
They come "calibrated" in different pressures. I had one marked for 34 lbs in the frot tire and 36 lbs in the rear tire.
Total junk. Various discussion boards on the Net concur with my assessment.