The Bellandaine

Any takers? All advice gladly accepted Philip

Hi folks, I’m looking for some advice on increasing an XV125 to a 250cc My plan is to swap the cylinders and pistons to 49mm bore set. The rest of the bike is pretty much the same as the 250 model so I don’t foresee any big issues. Question: Will I also need to change the con rods? Or will the existing 125 con rods work? Are there any other factors I should be aware of? Any advice or guidance is greatly appreciated. Thanks, Philip