If I race sport this season and am putting down endurance miles now, how long should the rides be? Most of these will be done on a trainer. I just blew my wad on a FS rig, can't afford a road bike and have a paranoia of road riding anyway. I have a pretty good tolerance however for the trainer. I'll read for 1.5 to 2 hours on it 3 x per week. Will this be enough to lay down a good endurance base before I can do more long rides on the trail when the weather turns?