I am ok if you don't post this but you should know. I brought a half bike because I could no longer run. My knees get very sore when I run. I had asked the question if I would be able to use the half bike with bad knees. I was told to read a review from one of the promoters and was assured it was a great activity for someone with dodgy knees. Apparently it would be good for my knees. NOPE. I can barely walk now without pain. My left knee is swollen to 1 1/2 the size of my right after riding the half bike two days in a row. I am gutted. Heaps of fun to ride. I was still trying to master turning. A very expensive short lived experience.