From:
https://www.africatwinforum.com/threads/dct-stuck-in-1st-gear.32747/"Have you checked the ABS sensor? It looks like the bike does not read it, i.e. the bike "thinks" it is stopped, hence you can't insert gears.
Try cleaning the sensor area and check its connection"
"Thanks. I will pull the rear wheel off again and clean the speed sensor and the pulser ring. I found a shop manual on line last night and it talked about being in first gear if the speed sensor went out and such. This was a simple tire change (well not really as I had to wrestle the beast) in the garage. I wanted to see if I could do it out on the trail. ??"
"I got it!!!! Thanks all of you for pointing me in the right direction. I put the flanged wheel spacer on the right side, which caused too much gap between the speed sensor and the pulsar disc, where it is suppose to be on the left side. Runs like a charm again. Totally my fault. Thanks for helping me out."