I can no longer find the web page, but I downloaded a great article a while back by Joe Guzzardi entitled "Teaching a Weed Whacker how to Fly". If you'd like, I can email it to you in PDF format. It is a very detailed article with great pictures on how to convert a Ryobi engine. Personally I have 3 Homie 25cc engines, one I bought already converted, the other two I did myself, following instructions I'd found in this forum. I'd like to try a Ryobi, but at this moment, I haven't run across one, other than the one in my existing weedeater......Hmmmmmm, I wonder if I can convince my wife it's time for a new one......