These are links to other sites that I personally found useful or interesting. (#1 3-wheeler site on the planet!!!!) (Best 81-84 Honda 250r site around! Devoted to only the air cooled 250r trikes) (best pistons around. I only use Wiseco in any performance build I do) (Best cam shafts and support parts around for cams and valve springs Some oversized valves available as well!) (great pricing on OEM Honda parts and even some performance parts still around for ATCs) (The BEST machine shop in the world! they do CNC valve jobs and porting, CNC boring and honing, and MORE!! Tell them I sent ya for a discount! They Recently got their CNC boring and honing machine, CNC rod bearing machine and Block boring machine for sleeving cylinders. So give them a call for pricing and the best work anywhere!!!