by ancker on Wed Feb 20, 2019 7:44 pm
I've done this a few times without issue. Granted, the last few times were just brake cables as I've switched to eTap everywhere.
I did this most recently on an Allez Sprint. So it's definitely possible.
What I did was:
Remove the cables (not housing).
Remove shifters, bartape, etc.
You should be left with housing coming from the frame and still routed through the bars.
On most bars you can simply pull the housing through the bars towards the frame from the frame side.
It's easy to tell the difference between shifter and brake housing, but not always obvious which is front/rear when everything is splaying out from your frame. So maybe put a piece of tape on the fronts to distinguish them.
Remove the old bars.
I found it easier to mount the new bars in the stem, but leave the fixing bolts loose enough to allow rotation.
Then carefully re-insert the housing into the new bars. This is the tricky part.
Depending on the bar's shape/contour/etc, the housing will easily find the egress hole, or you may have to fish it out. I've used a spare spoke J-hook with great success before. You might also try a hobby pick, grabber tool, or anything that can help guide the housing out.
Once the housing is routed through the new bars, install shifters and insert housing as appropriate.
If needed, I cut excess at the derraileur/caliper instead of at the shifters. I suppose you could cut at the shifter, but I've just not done it.
Then install new cables, then tune and trim/install cable ends.
Then if you're happy, new bar tape!
It's doable. But depending on bars it might be a fight to get the housing routed correctly. Mine have all been fairly easy with the spoke J-hook to help guide it.