Help trainer

Hi, I need some help.
I have the Rc120 bike (Décathlon) with 8 speeds.

I would like to buy a trainer. I want to take the “Elite Zumo” but it is compatible 9 speeds.
Some people tell me they provide tools for 8 speeds and others tell me it is not possible, it is not compatible.

So, I need your help…

I would think it shouldn’t be a problem to put a 8 speed cesette on the trainer


The kickr core ships with no cassette. Plenty of videos about installing 9 and 8 speed casettes on it. I “think” the necessary hardware ships with the core. You just need to buy a cassette and fit it. Worth checking on wahoo site to confirm. I purchased the Shimano 105 decathlon version for my kickr / zwift it’s a great bike for the roads too. Bit heavy but great as a backup