Just got my new Wahoo Kickr(2) two weeks ago, upgraded from a Bkool Pro, done a few rides and really struggling to keep up with my previous efforts from the Bkool Pro, my FTP is down abt 20% with the Kickr. (200 to 154)
Is this normal when going from wheel on to direct-drive trainer ? 50 watt difference seems a lot to me.
How do the numbers compare with real world performance? While the Kickr resistance unit is most likely accurate, the belt tension can skew the readings, much like the tension on the roller of the bkool or snap can. I wouldn’t be concerned with how the bkool compares to the kickr but rather how the Kickr compares to your actual riding. The ideal scenario would be to compare with power meter readings, if no power meter is available then review past real world ride data and see how it stacks up.
i tweaked belt tension so my Kickr closely resembled power meter readings. I tend to be about a mile to a mile and a half an hour faster on Zwift which I attribute to a number of factors like lack of wind, the “draft” effect but it’s somewhat realistic.
Thanks for the reply, unfortunately I don’t have a power meter to compare with.
It does feel like I have to put in a lot more effort compared to riding on the road, and I don’t think my fitness is so bad that I can’t hold more than 160 watt for 20 min 
Can see other people also experiencing issues with low or erratic wattage on the Kickr, so have just done an advanced spin down, as suggested in other forum, will test now to see if this changes anything.
I have the same issue. About 15% drop in power from the Saris Cycleops to the Kickr. Guys that I ride with on the road are 20% higher power than I am on Zwift, and I can’t keep up with them. I’ve resigned to riding on my own and doing structured workouts.