I recently picked up two YZ250's, they've been sitting for roughly ten years or so. One of the motors sat outside without the top end on it, the bottom end ended up being seized. A little bit of motor oil and some force applied to Kickstarter freed it right up. Everything in the bottom end seems to be working properly. Should I split the case and replace the seals?? On the second bike there's not much to say. It's basically a rolling chassis. My dad and I will be rebuilding both bikes. I'm not sure where to get all the necessary parts. Does anyone know where I'd be able to find parts? I'll be be posting pics as the build progresses. I forgot to mention when I bought the bikes the seller gave me three motors with 2 cylinders and a bunch of parts.