1. The 200 and 250 are completely different bikes. The 250 is based on a 1989 KX250, but the frame is made out of a cheaper, heavier alloy. The engine is basically a KX250 engine with different porting and a wide ratio tranny, so it has tons of performance potential. You can do an internet search and get all the info you want on the KDX250.
2.No one makes aftermarket graphics for this bike. OEM only.
3. The main problem with the suspension is the front springs are way to soft for anyone over about 140lbs. The forks will ride around at half mast, keeping them in the stiffer part of the stroke, making them harsh and unresponsive. Installing stiffer springs makes a huge difference. Stock is .35, I am running .41 springs.
4. The weight problem is mainly due to the frame, so there is not a lot you can do.
The bike has tractor-like torque that rivals (or beats) mant four-strokes, but it also has tractor-like turning. It is a brute-force bike that requires squaring off turns and steering with the throttle and rear wheel. It hates off-camber turns. If you ride in ares that have lots of slow, gnarly, technical hills, this bike will walk away from many others. It will grunt up hills in second and third that other bikes have to scream up in first and second, but the power stops early and abruptly. The engine does not make any top-end horsepower, although I am sure some porting would change this, but I like the grunty nature of the engine. You can loft the front wheel on demand in any gear except fifth, and it pulls very hard out of turns. This is a two-stroke that makes more torque than most four-strokes.
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1992 KDX 250-FMF porting,two-stage power reeds, Fatty pipe, Power Core silencer,titanium rod,Wiseco Ultra-lite, Pro-Action suspension...Oh my Gawd, they killed Kenny!