I love working bis... all sorts of fun stuff. I used to do a lot of Gable sets with a partner. those kill ya on anything.
(Pick a straight bar and a certain weight and do 1 rep then give to your partner. He does 1 rep. You trade off doing 2 reps, 3 reps, etc up to 10 and back down to 1 rep. Nasty)
Good way to mix things up.
When I had 18" arms, I was doing 8-10 reps with 110 lbs for 4 sets - no prob. Maxed about 135lbs or so.
Now that I am skinny again and my arms are down to 16" I had to lower that a bit. I now work out with 100lbs on an EZ curl bar for 3 sets at 6-8 reps. Pretty sad.
I also love mixing in DB Preacher curls, side cable curls, hammer curls... really keep it fun.
-j69