Holy crap. From the ground up.

[emacklin]

I had started having troubles with the right piston not firing in New York State. A bike shop there get it hot again (while fudging a few other things) <br /><br />Another stopover for a clutch issue (loose screws) in indiana. I can't remember if there was an issue with the piston at that point. I'm pretty sure it was running then.<br /><br />by the time I got midway through Wisconsin, I got cocky, and opened hte bike up on Interstate 94. It was hot, and I stopped using my brain. I think I pushed her up to about 85, when the trouble started. sudden loss of power. oil pouring out the breather valve on top of the head (all over my legs. nice and hot.) a lot of smoke coming out of the right tailpipe.<br />I pulled over to check everything out, and that's when I found that the right piston wasn't firing, again.<br /><br />I had to ride it to the next exit, so I pulled the plug on the right, and coasted about 4 miles at around 25mph on the left piston alone.<br /><br />The left is the piston with the carbon buildup, and the right piston (the one that wasn't firing) is the one with the hole.<br /><br />I'm not sure if the carbon buildup is just from the 4 miles, and tests during attempted repairs, but it seems odd that the right piston with the hole doesn't seem to have any build up at all, while the left is pretty well blackened.<br /><br />Does this indicate anything specific to you guys?

[LOUD MOUSE]

Keep the points clean and timed nuts on. I may be wrong but the piston with the hole looks to me like it was way advanced and overheated and the other was just along for the ride until it was the only one running. (may have been timed retarded also). .........

[piecutter]

My cb350 did the same thing, but it was due to an air leak at the intake boot. It's more common to see that on the 350 and other bikes with rubber intake boots, but it's still a possibility on the CB77.<br /> When you get it running again make sure you check for leaks by spraying carb cleaner around the intake manifolds while it's running. Any change in RPM's will be a sure sign that there's a leak.