Hi Snowy,
We talking engine or suspension here?
Suspension is where is start, just put a spring on the back of it. $155. Do the forks if you have another $155. Rear spring is an easy DIY. Forks are. Little harder, I’m sure you can find an OB who can help you.
Engine. The 250x is a great engine. The people who write them off have never owned one. I’m 115kg plus gear, Hobsy from ADB/Transmoto was 125kg when he owned one from 04-09. He still talks about it today as the best bike he’s ever owned. I had an 05 and still miss it. Better in the bush than my 10 YZ450.
I think they go ok stock. When the inlet valves start pulling through I put Kibblewhite valves in them, inlets only. You have to get the seats cut too. I can do it all, not expensive.
Run the stock header and muffler. They work very well despite looking and sounding ugly. Run an R muffler if you must change it. If you really have to have more power, stage 1 hotcam. More power everywhere.
Keep on top of the air filter.
I’ll add this last line as a catch all. The above is my opinion. If you disagree with me, that’s ok, I don’t give a shit. I’m simply expressing my opinion and will not be entering into an argument.
