Just picked this up:
1979 XS650E. Funny story behind it....
has 11k original miles. This teenage kid bought it two years ago, put tons of work into it;
repainted gas tank, put new mikuni VM 34s on it, then cafe-ed it out, bobbed tail, etc. Stainless steel brake lines.
After all the work, he became frustrated with it because it ran horrible. Back fired and sounded like gunshots when running, but barely ran.
His "buddy" the mechanic had determined that one of the exhaust valves was hung open, or bent or whatever. His mother was putting pressure on him to get it out of the garage, sell it or get it gone one way or the other. I traded him a 1996 toyota corolla for it because he needed a car.
got it back to my shop and found that he had not ran a gas line to the other carb. That was it. I see why he didn't catch this not just from being a novice mechanic, but the OEM carbs had an equalizer tube between them and the VM 34s did not. He just put the carbs back on and the single gas line.
I put a T in place and adjusted them, new spark plugs and it runs perfect. I can update with pics later after I get rid of the cafe setup, and replace the handle bar controls. I wrapped the exhaust too.
I've had a lot of bikes over the years but never an XS 650. Really happy with it and love the mag wheels. :0)