11spd cassette rubs on Raltech cover by default.
It looks like I might’ve finally cracked the issue of the cassette rubbing the Raltech disc covers due to their not being enough space behind the cassette. It was thanks to this blog post from Dark Speed Works.
Below is a copy of their guide for my notes. It’s for an 11-23T Ultegra cassette (DA doesn’t seem possible because it has a 2-3-1-1-1-1-1-1 config and I can’t find the individual sprockets to swap out the 3-block). The idea is to convert it to 10spd but with 11spd spacing and move the whole cassette out a bit.
“The solution on this cassette is slightly different from the previous two. You will need to buy a specific 17T cog for Ultegra 6800 cassettes (Shimano part no. Y-1Y917200). And you’ll also need two 2.18mm 11s cassette spacers for Ultegra 6800 cassettes (Shimano part no. Y-1Y953000, Shimano calls them ‘sprocket spacers’). Once you have these parts in hand, before mounting the 11-23 cassette on your wheel, remove the 17-18T sprocket unit (with cogs riveted together). If you drop out this sprocket unit and replace it with the 17T cog that you bought, the cassette will still have a progressive gearing spread (the same gearing that Shimano uses for 10-speed 11-23 cassettes). And one of the extra 11s cassette spacers that you bought will be used as a ‘behind-cassette spacer’ (see below). So, to create and mount the hybrid 11-23 cassette, you would put on the rear wheel freehub body, in this order:
one of the 11s cassette spacers that you bought (needed as a behind-cassette spacer)
the 19-21-23T sprocket unit (these cogs are riveted together)
the 17T cog that you bought
one of the 11s cassette spacers that you bought
the 16T cog
an 11s cassette spacer
the 15T cog
an 11s cassette spacer
the 14T cog
an 11s cassette spacer
the 13T cog
the 12T cog (cog has an integrated spacer)
the 11T cog (cog has an integrated spacer)
Finally, the cassette lock ring (properly screwed on).
When you’re done, you should only have the 17-18T sprocket unit left over. Properly adjust your 11-speed rear derailleur limit screws for this hybrid cassette, test it out thoroughly, and you should be good to go. (Save the 17-18T sprocket unit should you ever need to convert this cassette back to full 11-speed.)