So I recently purchased a new 11 speed wheel from Shimano. 2 questions:
1. I want to install a 10 speed cassette on the 11 speed wheel, which Shimano says is possible with use of the included 1.85mm spacer. However, some googling shows others have also installed the 1mm spacer in addition to the 1.85mm spacer. Today I dropped by the LBS, and the mechanic says adding the 1mm spacer would make it so that there are not enough threads for the lockring, but I'm a bit skeptical. Thoughts? I haven't had a chance to test ride the wheels yet because my bike is getting some cable replacements, but it would seem that my gear indexing would be off and I would be able to feel the difference if the 1mm spacer was needed.
2. When going from a 12-27 (current setup on current wheels) to a 11-28 cassette (new setup on new wheels), will I need to have a different length chain? Intuition tells me no, but I'm no expert.
Any help for this newbie would be greatly appreciated, thanks!