I have a 750 and they were just plastic caps stuck into the ends...I put a rag over my ends and just used some wide plyers and pulled them out...i know it may seem anal, but i used the towel so i would not leave any marks on the plastic ends that were in there...in case i wanted to put them back in if i sell the bike in the future...although I dont think that is going to happen anytime soon!
Went out to my S4 this weekend- has different barends than yours - and started trying to get the out with the allen wrench and it was stripping the bolt. So I took a vice grip - clamped it on to the bar end and started spinning that - thinking that might loosen the thread or something.
No luck for me either - I still have to try letting some WD40 work its way into the bar ends and will try again. I just don't want to strip them and have to drill them out.
I wanna get my mickey mouse ears out and put the Napoleons on darnit.