any big bore kits available for my old 250 big red and maybe some bigger wheels any help would be cool.

 

Check with Powroll.com,they have might have something.

 

I don't know about any big bore kits, but you can get oversized piston for rebuild, possibly higher compression, cams and heavy duty spring from web cams, and aftermarket exhaust from Cobra and probably one or two others. DennisKirk.com has the exhaust and pistons, and you'd need to get in touch with Web Cams for the other stuff.