Rear wheel size

My 06 KTM 300EXC has a standard 18" rear wheel. After last weekends 3 hour enduro, the wheel bearing broke up and damaged the hub. If I can't repair the hub, I might have to get replacement wheel.

Most of the ones I have seen on ebay etc seem to be 19" rears?

Apart from the obvious answer of "one inch", what are the differences between a 18" and 19" rear? Would a 19" fit straight on to my bike?

Grateful for any advice.

Finding a road legal tyre for trail riding is very difficult on a 19" rear, I would not fit a 19" wheel.....
Get on to the ktm uk forum and put a wanted add in there..... plenty of bling merchants get rid of there oem wheels and fit Talon/Excel stuff.....

Timpo.