after around 9 sets for bi's my pump is gone and I just feel no point in training them further. since i stoped doing that i put inchs on my arms.
This was true for me as well...it seems the less i train biceps the bigger/stronger they get. lately i've been doing 6 sets after chest and they are making awesome gains. i can get 8 reps per arm with the 90's using a hammer grip at the end of my bicep routine.
2 warmup sets of BB curls - 15 reps
2 sets of standing BB curls, shoulder width grip - 8-12 reps
2 sets of seated alternating DB curls - 8-12 reps
2 sets of heavy hammer curls standing - 6-10 reps - i go all out on these
that's it and i've made better gains like this compared to anything else...it's my modified Max-Ot program.