The KTM 50 SX Junior is 23 inches, the 50 SX Pro Senior is 25.6 inches.
KTM 50 tops out around 50-52 mph my 06 ktm 50 hits 55-60mph
85 mph
As far as I know, there is no adjustment.
You can find that info , as well as a lot more, here: http://motocross.transworld.net/2003/07/09/2004-ktm-125-sx-200-sx-250-sx-and-525-sx/
about £1400
The sx is for supercross.
under the gas tank
In the center of the head (on top of the cylinder).
The KTM 360 SX is still a good bike, like all other KTM's dependable but parts are expensive when you need them. Here is a link that has pictures of the 360 SX: http://www.bikepics.com/ktm/360sx/
The KTM sx is fast but the yfz is the best for what I do, what kind of riding do you do?
Stock, in the ballpark of 48-50 hp