I really want to hesitate to give away my secret. On the other hand, I don't think we have too many other riders here that race a i-magic or fortius during the winter, so I'll be nice and give you the real deal on how to escape the tire slipping. It is called automotive belt dressing. I simply spin the tire slowly and carefully give the tire a mist of the belt dressing. You will find that you can run higher pressure in the tire and loosen the tension further to have the smallest possible contact area on the drum. When doing online trainer racing, you need every bit of help you can get. I've gotten rid of a good 30 watts of extra friction this way so I can apply it to the actual race and not loose it in slippage and extra tension to overcome the electromechanical brake system.