Can't pedal on group ride

Hello, 

   A rookie on zwift, first FTP test this morning, was going great until I hit 230w for 1:00, I just couldn’t get the pedals to rotate and it sounded as if the rear wheel was slipping…so I logged out, tightened up the tension and then got on the Volcano course for a group ride with 63 riders, same thing happened again…hit 230w for 1:00 and just couldn’t get the pedals to really turn…

  So I logged out, got back on and just hit “ride” doing it by myself I cranked it up to 460w with no slipping, no hard pedaling, so I am thinking I had to be doing something wrong on both the FTP test and then the group ride…I just signed up for the event and started out and it was great until I hit 230w and the pedals just barely turned over – even if I shifted down to a smaller gear. 

  I am just wondering what I am doing wrong. 

What trainer are you using? More info is needed to assist you.

oh thanks, I am on a kinetic road smart trainer…I just tried another group ride and saw that it defaults into ERG mode, so maybe I don’t have to or should not be shifting on a group ride…although if it was a race, (which it wasn’t) but if it was I’m assuming I would be shifting :slight_smile: It’s a bit confusing to me, really appreciate your insight…you seem to be really dialed in on this…because you have helped me before on a drafting question.  

 I was doing the :45 minute FTP, wheel started slipping at 230w and everything is good, tension, tire pressure etc. – although I turned the tension up a quarter of a turn anyway, joined the group ride to see if that made a difference, still couldn’t pedal at 230w, left the group, rode solo and hit 430w on a sprint on the flat volcano course, with no slipping…so I am thinking I am doing something wrong on the FTP and group ride that may be ERG related?