HH is correct. I currently own and ride a 9-speed road bike (with an extra wheel with ultegra 9-speed cassette used on the trainer) and plan on buying a tri bike in the near future. The purpose of my question was to figure out the feasibility of using this wheel on the trainer with the new tri bike (likely to be ultegra 10-speed). Sounds like I’ll be okay with the 9-speed wheel on the 10-speed tri bike since all the bikes I’m looking at have bar-end shifters with friction mode.
And no worries about the hijack. It was on topic and ultimately gave me the answer to my question. Thanks all.