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Loud consistent pop pop pop

Donovan_ge

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So this is my first post on here so give me some slack. I just got my 1979 cb750 cafe and it's been a hastle from start to finish. Most recently I was traveling on the highway and was push 75-80 mph and all of a sudden a very lowed and consistent 'chopping' or 'pop pop pop' noise started and I lost a ton of power. I have a video of noise but..
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Lost a cylinder but it could be due to a lot of causes. Pull plugs to possibly see which one it is.

Looks like you need to tighten your chain. Good backdrop there for a Hollywood movie..........

Might check if the alt is charging, these are well known for the alt rotor going south with no warning, it first shows by engine beginning to pop out of nowhere (battery low) if you haven't had to crank electric start in a while.
 
So following up on this. One of the spark plugs was completely out. Got it back in and the popping stopped. It's coming back a little because the book and the plug aren't 'clicking' together. I bought 4into1's deluxe tune kit to redo the carbs and plugs. Wish me luck
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If the plug physically came out of the hole then the threads in head may be damaged. The extra looseness lets the plug settle down tight crooked to not seat correct and tight all the way around, then ignition forces knock it loose and spin it out. That force generally will overwhelm any boot snap-on force, talking about a small hammer hit there.
 
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