Originally Posted by
HiBoost
I don't think that is true. This is the reason they put the 3rd party bar end shifters on there in the first place - to address the lack of OEM compatibility from Shimano. In other words, starting with 10-speed, Shimano road and mtb shifters and derailleurs are no longer interchangeable. So you can't have a 10-speed 11-34 mtb cassette and derailleur with a 10-speed road STI shifter. And if you went with an all-road 10-speed setup you'd lose the gear range you need for a touring bike.
Good point, I forgot about the whole 10 speed compatibility issue.
So a 9 speed long cage rear derailleur and a Tiagra triple front derailleur mated with Tiagra shifters. That would allow the 10speed cassette, chain, and crank to remain. The 9 speed RD doesnt care if its mated to 10 speed STIs and the road FD would have the correct pull for the front.
Or get some Tiagra STIs and add a JTeK Shiftmate 7 connected to the FD and a JTek Shiftmate 6 to the RD. This would allow the stock Deore components to remain.