1- tough issue for sure. i have bar ends on 2 bikes and am in the process of adding them to a 3rd. Ive never hit my knee on one of the shifters. Not sure how the geometry works for that to happen while still fitting the bike, but its for sure unfortunate since you have to spend $ and time to create a fix.

2- Look into a new rear derailleur like the Shimano Deore RD M592 long cage. Basically, a 9 speed long cage RD.

3- Ive read about that Wolf Tooth option already mentioned. Companies come up with workarounds for all sorts of incompatibilities these days! Its almost as if the manufacturers segmenting their products so much is a pain for the consumers...but thats another topic for another time.

4- Shimano 105 5703 Triple STI Shifter Set | Chain Reaction Cycles 105 triple for $150 and free shipping.
http://www.amazon.com/Shimano-Tiagra.../dp/B005DVJ2XC older style Tiagra for $130 and free shipping.


Good luck!