[RockBit]

If you had air still in the system, the pedal would not get firm on the second pump. It sounds like you have bled the system adequately.

A residual pressure valve is made to cure the problem you are describing, and you have added one to the rear brake line. Either you have installed it backwards, or the one you have is leaking. Either condition will allow your rear pistons to retract too much and give you more pedal travel on the first pump. Since the second pump is firm (the rear pistons have not had time to retract) my guess is your residual pressure valve is leaking/faulty.

I would try a new residual pressure valve. My 2 cents. Good luck.