newbie needs help


So far i love my Trek Bruiser, so far the only shank piece is the Bontrager seatpost, it won't stay tightened for anything, so i'm looking at new seatposts, and the seatpost i have now is 29.2, the closest i can find is 27.2 and 30.9, would either of those be fine, i'm new to this so i'm unsure as to what would be alright. PLease help. Thank you



I guess i probably am a heavier rider sitting at 215lbs, which is probably why the seatpost won't stay tightened, the two seat posts i have in mind are the Race Face Diabolous and the Thomson Elite Aluminum, both are the same price at price point and they seem to get pretty good reviews, but help on the size woud be awesome

never mind i'm a moron, i found a spacer to fit 27.2 to 29.2, thanks for not bashing