I ride with a group that goes anywhere usually between 35-40 km/h on the flats. The hills are anyones game. Ive been riding for a year and a half and I go on the rides to get faster. My first ride I got dropped about half way through. Now when I go, I can stick with the pack the whole ride, but I only pull once or twice. I usually go to the back when I'm second in line. This is working well for me and I found myself getting faster and being able to feel better for longer on the rides. My last ride with them a couple of weeks ago I in the group for the sprint, but got dropped about 100 meters before the sign we sprint for. So basically what I'm saying is just keep going on the rides, never skip one and you'll get better with every ride.