125 to a 200

[GASGAS18]

Ive been told if you just change the head and a few other things, you can change a 125 to a 200, 200 to a 250 etc. How much is involved and is it expensive?
Reason being I can buy an 01 ktm 125 exc in mint cond. Freind of the family owned the bike, and rode it literaly 3x. Not even a trail scratch. He said i can buy it for like 2500 which is a good deal, but i dont want a 125. Id be happy with a 200 which is what i have. Any comments?

 

[Layton]

You would need at least the crank, rod and piston. Probably a different pipe also. I wouldn't do it because by the time you get done you could have bought a good 200.

You can't change a 200 to a actual KTM 250 because they are a totally different engine. Of course you could modify the 200 by boring and or stroking it to a larger size but thats usually not worth the money and effort either.

Hope this helps.

 

[yota]

cylinder, head, crank, pipe, ignition, head stays, piston and rings, carb (it will work though). I did this. It was a fun project but but would be expensive. I had a 98 200 mxc and an 02 125sx so I just swapped the parts I needed although I bought an 02 200 cylinder and piston cause I wanted the 02 porting. I then sold the 98 as a 125 (with almost new 02 top end and crank).