It looks like I will be changing air filters. My rings failed this week, so I decided that while I had the cylinder and head off, I would go ahead and order the 70 cc DR kit. I will be using a bigger carb with a bigger jet, and will need a better exhaust and air filter too. I've been playing around with trying to make my own. I want one that I can wash out because there is lots of dust and dirt roads where I live. Also want it to be small so it won't be in the way. I'll post a photo when I get 'er done... could be next week sometime.