I see in the specs that the x-seam range is 36"+ to 45"+. I am 5'10" with a 43" x-seam. I am not thinking that the boom on this trike needs to be shortened to fit anyone that is normally proportioned. Nor does there need to be any pool noodle placed to hold the rider back, because with a decent amount of recline, the seat will form a natural 'bucket' for the riders ... yeah. So ... we really need to see the o.p. on this trike. It may be counter-intuitive to want to stretch out and be all vulnerable to the worlds gaze but being scrunched up on a trike is just as bad as being too stretched out. There are published instructions online as to how to measure x-seam. There are probably videos as well if you are more of a visual learner. If you 'start' your explorations for fit on the trike with the results of your x-seam measurement off the trike, you may get better results.