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First Post - 1978 CB750K - Project Start

So I've run a boatload of Sea Foam through it, in the fuel, in the oil, spray directly into the carbs. I retested my compression and it's at 120, 120, 110, 120 across the board now. The original results were around 90, 90, 60, 90, then I added some Marvels Mystery Oil and it came up to 160,160,90,160.

I cleaned out the master cylinder with compressed air and then topped it off with brake fluid. Tried bleeding the brakes the first day but couldn't get it working. Went to give it more attention a few days later and it looks like the fluid did some of the work for me as I was able to bleed the brakes. They aren't great, but they are good enough to do a short test drive which is more than I've gotten to do yet.

Took it for a spin around the block and noticed something odd - the rear brakes work when it's off the center stand, but they don't when it's on the center stand. Is this normal behavior?

I gotta say I'm thrilled that I've made it this far this fast.
 
That is odd. The rear brake should work whether its on the stand or not. Maybe something is binding. Does the lever have full travel when its on the stand?
 
Weird. The only thing I can think of is that when it is on the center stand the swingarm drops just enough to increase the travel to engage the shoe. Can you wind some more adjustment into the rod?
 
This could be it... I hadn't taken a look at the adjustment rod...

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That picture of that rear brake rock setup is scary.

One could say it's a bit 'nuts'...

I assume I should pull all that crap off and replace it with the appropriate bits. I've found the parts on e-bay to put the end of that rod back together right.

I'd assume I adjust the rear brake arm as far back as the rod will allow, but my Clymers doesn't really say.
 
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I would also check the condition of the brake shoe. Someone was obviously trying to "fix" a problem with the rear brakes. If I remember correctly the last nut on there with the concave face should sit against the brake arm pin.
 
It was raining last night so I didn't actually work on the brakes, and I'm going on vacation tomorrow so packing tonight...

According to Clymers that nuts on backwards, the U should face the pin. I'm not sure if that pin is there or not, same with the spring thats supposed to be on the other side. Worst case I can get everything including the rod for ~$40.

I'll check the drum and the shoes. Going off the advice of several here I'm going to ride the bike this summer (after front and rear brakes are totally redone) to see if I uncover any other lurking issues, then this fall start the total tear down and build up process.
 
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