I beleive the KDX is a lot cheaper, but the goodies that come on the KTM is first rate.
You will spend the bucks to change all the parts on the kawie like chain, sprokets, handlebars, perhaps a steering stablizer is in your distant future with fat bars, well you wont have to change the top claimps on the KTM, check out the wheels on the two bikes, guess who's got the better rims ?
The KDX is alot heavier too. Lets not forget the suspension, like above the KDX will need alot of work to go fast on esp. if you go do some MX. Quik release side panels, lots of options from KTM as well that you can do to the bike, tanks, gearing,. ext
I have had a KDX before and I did like it to a certain point, when things got alittle faster the bike got a littler more harder to ride. A freind has one still with a modified suspension from White Bros., I think it handles worse now. (like a slow old 250)
Ive never tried a GasGas 200, alot of riders really like them. Just might be harder to get parts than a KTM.
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01 YZ250F
92 KX250, adios amigo!