You mount the "cycle" like you would any bike. There are two sets of grip handles, one closer for those with T-rex arms like myself, and one a bit further away for longer arm lengths. You pull these grips towards you which causes the back of the restraint system to come in contact with your body. The device will lock in this position and obviously the CMs check that all is secure and tight enough. I saw a few fluffier folks ride without a problem as did several kids. It is a really neat set up, in my opinion and seemed to be forgiving for most body types. I can try and track down pictures, if you would like?