Bike sizes

[eece]

When it comes to mountain bikes, is it best to have 2-3 inches space between the top tube and you with both feet on the ground? I'm 5'6, with 28" inseam, and as I measured my current bike, the frame is 15"... how does the frame size relate to your inseam size? Sorry, I'm learning here

[Nobody]

Stand over height doesn't really matter that much. It's the reach from the saddle to the handlebars which is more important. This is mainly defined by the frame's effective top tube length (ETT) - which is the horizontal measure from the head tube intersecting the top tube, to the seatpost - and the stem (which is easily changed).

[il padrone]

Standover height matters.... for your goolies! On a normal road bike 2" is about the normal minimum for comfort. Yes, you can get away with even less, by always stopping and hooking just one leg down with the other leg drooped over the top tube, but it's inelegant, awkward at times and not so handy.

On a MTB the standover needs to be even greater as you may be forced to stop on a steep descent. When this happens your reach to the ground is very much at an angle forwards and thus much greater. Typically standover heights of 5"-7" are not uncommon at all. If your MTB is to be used for trail riding in mountainous terrain you really need the extra clearance if at all possible. For shorter riders it sometimes is just not possible, but best to be aware of this need when choosing a bike.

[bychosis]

stand over height matters a bit, but still the most important part of the fit is top tube length, and also seat-pedal length. If you aim purely for standover height the other two could be out and you wont fit the bike while riding it, but you'll look great whilst standing over the top tube at the end of a ride.

Most proper moutain bikes should provide you with decent standover if you have the right frame size

[il padrone]

but still the most important part of the fit is top tube length, and also seat-pedal length.

I don't think I said anything to the contrary of this . The OP's question was about what the best standover for a MTB is and I'm suggesting that 2"-3" is inadequate.

[Mulger bill]

Spare a thought for us short legged, long torso'd riders. I bought my TranceX on the basis of TT length as I don't like leaning back to ride a bike. The TT just brushes the lads doing the standover test. My hardtail is long AND low