When I read your post, I see references to up to 800.
Obviously the 250 is totally not in the same ball park, no matter what upgrades you do.
From my perusing of the scooter forums, 2 strokes seem to give the best performance increases.
If you are very diy, and there can be bonding with your son with the performance parts upgrades, go for it.
Personally, that is a lot of work, and one cannot hit the trails while rebuilding.
IMHO, in conclusion, rather get a Kymco mxu450, as there are lots of references here on this forum, of how awesome they are.
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