Knee pain after switching turbo trainer

I’ve been doing indoor training consistently from the start of the year and everything has been going great. A couple of weeks ago I upgraded from a Kurt Kinetic Road Machine to a KICKR '18 and after a couple of workouts I’ve started developed pain in the rear of my left knee on the outside.

There’s a couple of things I think might be the cause, but I wanted to see if anyone’s experienced similar or how likely they are. Firstly, getting a new trainer resulted in a slight increase in training volume. Nothing crazy, but definitely more than I’d usually do indoors in a week. The other change is that I’ve moved my setup from the living room into our spare room which, given that our house is over 100 years old, has quite an uneven floor. I’m not convinced that my new setup is perfectly level (even with the KICKR’s adjustable feet) and wondered if that could be contributing?

Is it normal to have to take things slowly when switching to a new type of trainer?

I went from many years on a kinetic to a kickr a few years back…the transition hits when it went up in watts or hit a steep hill in zwift just killed my knees…that and having to maintain higher cadence than I was used to caused by my knees to hurt.

Are you training in ERG or Resistance mode on the Kickr?

Mostly ERG rides in TR and a couple of Zwift sessions in simulation mode

I would take the time to get a level and make sure the trainer is close to level. I had a lot of weird strain on my legs when my kickr was off level after moving to a different place and everything was resolved after getting it sorted. Another thing is to just double check things like cleats and pedal tension could be a little wiggle that is throwing you off when putting down the power

Depending on the gearing you use in ERG, you might be experiencing different muscle and tendon strain compared to the old trainer.

Thanks for the suggestions all. I’ve spent some time making sure that everything is as level as possible on the trainer (both pedals and the seat are now perfectly horizontal and there’s no trainer rocking side to side. I’m also going to try ERG mode using the big ring instead of the small one as I think that’s more similar to my old Road Machine?

Either way, I’m going to take a couple of days rest as there’s a little bit of inflammation in the back of my knee and I don’t want that to cloud my testing.