Buy a cheap V-brake noodle and pull the liner out of it, I have also pulled short pieces Teflon liner out of cable housing but the noodle liners come out much easier. You might also consider an application of dry film lube if the Teflon liners won't fit.
Back to our derailleur/shifter discussion of a few days ago, I stumbled on the correct flat bar shifters for my R443 front derailleur! I was on FB Marketplace a couple days ago and there they were. The seller had apparently bought a new 3 X 9 flat bar road bike a few years ago and decided to swap out the flat bar cockpit for drop bar not long after buying it. He pulled the flat bar setup and put it in storage until a few days ago when he decided he wasn't going to use it again. I not only got the shifters in like new condition but a nice set of Avid V-brake levers and the 31.8mm road flat bar. I've decide to use the R443 FD and SL-440/441 shifter setup on the T-900 with the original Deore RD instead of the Deore XT derailleurs and shifters, I'll save them for something else..... There's ALWAYS something else LOL.
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