Gary,
thanks for that. you have an rp23 with the ‘5 tune’, low compression?
it’s not that big a deal but as i normally ride a single speed i’m well used to standing up, and i had thought that the rp23 would allow me to do that in a slightly more controlled manner than i am getting now. if i look at the frame when i do stand the movement is pretty minimal but of course you can feel it. understand that FSers work better sat down and am happy to do that most of the time, but when i get tired i revert to type!