I have had cornea transplants and finally have new glasses on the way. Having a lot of trouble reading fine print on my computer. I have tried searching, going thru all the threads etc. Making my head hurt!!!
I feel like a newbie! I pulled the carb, freshened it up and measured the throat (air filter side) at 56mm. The only filter I found was an Emgo 54mm. Price was cheap enough in case it won't stretch on. Not a crisis. Will know if it fits in a few days. Would prefer a better filter but I am anxious to keep building while I am in the mood. Thanks guys!! And gals!!

For those of us who have to have glasses, one problem we have to deal with is the helmet touching the temple pieces. The helmet is Gonna vibrate, and if the padding touches your glasses, it's gonna shake Them.
So, once I figured that out, I took my upholstery needle package out and grabbed the small curved one and stitched the padding down tight along the line from ears to eyes. It's much, much better.
Just reach up and gently move your glasses around. The world moves.

Full disclosure
The above statements can be run through a BS detector/filter that would make a Reverse Osmosis system look like a chain link fence and they will Still remain unchanged.