Without looking at my cadence constantly, I'll usually end up around the low to mid 90's rpm for my comfort zone. Slower for a very long period of time and i'll start to feel it in the quads and get to 110 or so and I'm on the verge of bouncing....but I'm working on it.

Usually, if I have to ride my trainer, I'll use a recovery day to do a few spin ups to work on leg speed. I also have days where I do 10 min intervals at mid to upper 80's trying to build some leg strength without killing the knees