People have mentioned problems with the cable spools on their SRAM drop bar shifters. Maybe they have also damaged them, I don't know, I've never seen pictures of them.

This is a replacement cable spool for the late generation 10 speed and all 11 speed shifters with the original red cable spool.

This should also work for upgrading any shifter to 11 speed if you have the 11 speed gear ratchet- maybe received from someone who has upgraded their shifter with a 12 speed gear ratchet. With a new style gear ratchet- 10, 11, or even 12 speed- this part should even work on older 10 speed shifters with the white cable spool since you're not going to be using that spool anyway. The gear ratchet may need to be filed down as illustrated or it might hit a corner of the shift lever and not stay in the lowest gear.

This is a remix of my cable spool for a Shimano derailleur- which is why the Fusion360 model has a bit of cruft to it left over from the original part. I have not tested this particular part yet because my shifter currently is set up different.

The holes are oversized to cope with my 3D printer's quirks. If they are too oversize for you, the size can be adjusted by changing the user parameters "HoleCorrectionOffset" and "LesserHoleCorrection" in the Fusion360 file. Likewise, if the spool measures out to be the wrong size, change the "SmallerPulleyDiameter" or "PulleyDiameter."

V2 of the files have minor changes. It has shallower lettering so it should only be one layer thick. There is also a crossed out portion on the underside where the gear ratchet shouldn't cover (since it's possible to put on rotated 180 degrees, which you'd notice when reassembling the shifter), and the cable head has been moved closer in so there's more plastic supporting it. I don't think anyone really needs to use the original versions, but I've left them in case there's a problem unanticipated by my lack of imagination.

Print at whatever layer thickness you prefer. I usually do 0.3mm, but it still doesn't take that much time even at 0.2mm. I like to do 100% infill just because the part will be slightly compressed. I usually use ABS, but the part pictured is PLA.