xr80, or crf80

Whatg ever honda is calling them now. Its what I started on as a youn pup, and held up very well. Crashed it alot lol

 

pssh.. she will prolly get bored with an 80. Better get her a 1000rr.

 

+1 on the Honda 80
You can of course temporarily cut the power down a bit Voodoo by playing with the throttle cable and carb stop, until she's used to it, then return it to std.
My buddy did that for his 8 year old, now he's unstoppable on the thing, having a BALL !
I wuldn't buy the Korean bikes, we've had them here for a few years, and they don't take abuse well at all.
Buy a secondhand unit, so when she crashes it, it doesn't matter, then later a new one if she (and Dad) like the idea.
My 2c worth

 

i had an xr100r, it could keep up with a polaris trail boss 325 atv around my trails.it was a great bike. five gears. the new ones ares called crf i believe

 

Very cool Voodoo.I would also suggest the 80cc, with her size i think a 50 would be a bit small. I would think with her size if she can drive a horse, she can drive a dirtbike

 

Ok now your talking about what I know alot about-small dirt bikes. I just got a 2005 Honda CRF50F for stunting and putting around the yeard. It's a very small bike and she would not like it since she will not get the whole pocket bike thing. You want to stick with a 4-stroke semi-auto clutch. The semi-auto lets you shift, but there is no clutch to pull in or use to take off and stop-you just click it up in gear and go then let off a bit and shift to the next gear. A Honda CRF70 or CRF80 would be a great bike for her and you will even have fun on it. The early 2000's were called XR's but are the same as the CRF's just not so good looking plastics.

The Yamaha TTR90 is a great bike as well and even has electric start. All bike I listed have a good after market support if oyu want to upgrade the bike.

 

Another vote for an xr80--I got one when I was 6 and flogged the thing until I was 12...it never broke--and I abused the **** out of it.