http://www.ebay.com/itm/80-83-YAMAHA-XS650-CARBURETOR-SLIDE-PISTON-RUBBER-DIAPHRAGM-22-3F7DP-/142430820604?hash=item212989d8fc:g:XuMAAOSwVJhZVfC0&vxp=mtr
Awesomatious! If you're interested in details, read on.
This is an inexpensive diaphragm and piston combo for BS34. It is similar to...