So my dad used to have a burgman 400, and when you got to where you were going you could stuff everything under the seat. You could fit a small child under that seat. Now I have my gs500f and there's barely enough room for the paperwork under there. What do you do with your jacket, helmet,  gloves, and pants?

I just got a giant topcase for this reason.

Like a dork, I carry all my stuff around with me.  Sometimes I used a tank or tail bag, but I would worry about those being ripped off with all my stuff.

There are two helmet locks under the seat you could use.  Otherwise, many folks carry a backpack that'll fit their stuff, or a tank bag, or tail bag that you can carry along... Or have a topcase or saddlebags you can lock up.

- Bboy

I have an Alpinestars tank bag my jacket and gloves go in. Sometimes I will put my gloves behind the gauges. I NEVER leave my jacket and ESPECIALLY my lid anywhere.

A Shoei X-Eleven new is probably 600+ and a then SENA bluetooth I have is another 160. So it never gets left anywhere. I will gladly carry it with me

backpack,....helmet on bike,.....my bread always gets smashed coming back from heb,...farg

If your in a safe area I would always use the helmet lock. I sometimes would hang my backpack (with a luggage lock) from the helmet lock as well so store stuff.

Most places I go require that I keep my pants on however 

I keep all my gear on/with me. I just dont trust leaving anything -especially my helmet- on the bike.

I do have a tankbag i carry around aswell, in case i buy anything, and it carries some stuff i like to always have with me (multitools, medical pills, etc) i dont care if i look stupid or get hot.

get a top box that will hold your helmet, jacket, and gloves.

top boxes ROCK.

oh, also, the burgmans rock too.

Helmet and gloves go in the top box, leather jacket in one side case, leather pants in the other side case. All locked up.
Hard cases are great on long trips, but for commuting they are basically my mobile locker.