.. who likes riding frames that are far too small for me on paper?
They just give me more confidence. What am I doing wrong?

It's starting to look like you are. I can't offer any more useful insight as there are no frames that are far too small for me.

I do. Well my Tricross is an XS and I am 5'7" with a 30" LEG

Me too. 5' 7" and don't ride anything bigger than a 16" off road. As an instructor I see lots of folk with bikes that are too big for them.

It's getting better but some of the lower end of the market still consider an 18" frame to be a small 😯

ME too – I'm 6'3" and anything over 19" feels wrong. Always have 400mm seatposts on minimum insertion.

At least some people came out of the woodwork eventually!
I don't feel cramped or anything, but all this talk of top tube length makes me feel like I am doing something wrong. Is there actually a disadvantage to using a 400mm seat post all the way out?

You can alter your effective TT length by altering your stem, bars and saddle position so I wouldn't get hung up on that too much. As for running a 400mm post fully out, it will put greater strain on the post and frame but as long as you're within the post / frame guide lines you shoud be fine … I've not split a frame or snapped / bent a post yet.

I'm 6'3" and my M4 S Works hardtail is a 19 inch, it doesn't feel cramped and there is still loads of seatpost left. Small frames give you more confidence (more top tube clearance) and in theory they are stronger as well.

My frames have been getting smaller.

Cotic is a medium, so is the Chumba. I'm just shy of 6'.

Used to run the Cotic with the saddle way back on the rails. Now its middle and I was thinking yesterday about how it would feel with a 70mm stem as well…

First mtb (waaaay back in the day) was a 23"!

5'11 and 16.2 inch frame. 22.5" TT

I don't run my post as high as most.
The bigger the frame the less fun for me.

I was about to say that I don't rum a frame too small

but I always run a 330mm post on the min insertion mark. I'm glad to hear people do the same on a 400mm post. Maybe I could get a cotic Soul to fit. I'll get the tape measure!

I'm 6'2" and I've got 17", 16" and 15" frames, I don't know why but a 22.8" top tube and a 50mm stem just feels right to me.

I also remember having a 22" claud butler catalogue bike when I was a kid which I sold to a short ass mate, I think it put me off 'gates' for life.

I'm 6ft with a 33" inside leg and ride a M stiffee. I've never had a frame about 17.5".

You can alter your effective TT length by altering your stem, bars and saddle position

The way I see it the Effective TT length is fixed the moment the frame builder cuts the tubes
The effective top tube length is the horizontal distance from the top tube/head tube junction to the seat tube.

5.11 and ride a 16, tis just more fun

UPLINK you pedantic git 😉

I'll clarify and say the relative TT length rather than effective.

Me too, far happpier on a frame thats on the compact side.

Saddle keeps being shifted forward.
Stem keeps getting shorter.
Bars keep getting wider.
That's me.

UPLINK you pedantic git

😀

anyway – smaller frames are great for a couple of hours in the woods etc.
I need a bigger frame for all day epics though

I don't often go for more than a morning (around 20 miles). As long as I am enjoying it I suppose it doesn't really matter!
I would have thought that smaller frames could be lighter too.. so why don't you see them being used more, or different size frames only really having a longer effective top tube length?

Depends on what its for, road bike is "correct" size, wee jump bike is tiny, all purpose 5" mincetank is somewhere in between.