HELP,,,,,,,,Soft rear brakes on 2002 RSV

[maddog2498]

I have a 2002 RVS, with 135k and my rear brakes are soft and will not slide rear tire. I put new rotary on rear app 40k miles ago when I put on new tire, and they were a little soft but would slide wheel if I tried. About 16k miles ago I put on new rear tire and when I got it back together they, I bled the brakes, but they were a little softer than the last time, but I could still slide rear if I tried. I just put on another rear tire. This time I use a 1 man vacuum bleeder and still pump brake to bleed them the best I can. When  rode today I could not get the rear brakes to slide the tire. It has stopping power but very soft. Now the rotor that I put on was an after-market. I notice my old OEM rotor was app 7mm thick and was worn down to 4mm. The new after-market rotor was only 4mm thick brand new. Do you think this is my problem. Any help and advice will be appreciated. thank you