Forget riding that YZ 125 in the woods. What a pain....I know because I did it! I made my YZ125 about as good as it can get in the woods. And it still was no match for either my CRF250 or my KTM 200EX/C.
The YZ 125 is for the track....it doesn't have the torque and smoothness of power delivery needed for trail riding. The YZF/CRF/RM-Z/KXF can do both pretty well. I'm no 4-stroke fan but having owned both at the same time (YZ125 and CRF250) I know which one is better for all around riding.
MXN
i agree 100% , not only that but it's not really that good for the engine if you plan on running alot of trails on the 125 because your alternating too much in rpm's and it's hard to keep the RPM's in the band with a 125 2 stroke on trails..wich we all know is not good for a 125..
KTM has trail/enduro/woods riding dialed in with the XC-W(e) range - the 200 / 250 /300 2-strokes are light, tractable, fast and a general blast to ride.
I would pick any of those over the CRF250R in the woods really....a little bit more effort/skill is required to ride the 2-stroke but it's more fun in my opinion as well as lighter.