Bike too small?

[Patch1875]

I've got a giant terrago mb with a medium frame.

I'm 6,3 14.5 stone and fit the ok I think, seat up quite a bit but I noticed the back tyre always seems a bit to flat when I sit on.

Question is,is this bike really to small for me or is the tyre issue something else?

You will have noticed I'm clueless about bikes.

[nammynake]

One companies medium is another's small is another's large, but generally I'd say medium is too small for you. However that has nothing to do with the tyre being under-inflated. Solution - put more air in! If these are standard 26 inch mountain bike tyres you should have around 40 psi. You can go lower but it depends how heavy you are and what kind of riding you do. If you go too low you risk pinch flats.

[Patch1875]

Cheers, feel the tyres are pumped up fairly solid but it's just a crappy pump will have another go.

[Gizmoish]

Tyres always squish a bit: but read the sidewall and inflate to whatever the max pressure is: buy a foot pump from Halfords or a proper track pump.

I'd always rather ride a bike that's slightly under- than over-sized, as you can buy longer stems, seat tubes etc.