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79 CB650 Running only on 3 Cylinders

Posted: Sat Jul 08, 2017 12:10 pm
by cpower
Okay newbie motorcycle owner.

Only 3 of the 4 pipes get hot when idling prior to riding (When sitting on it, it's the 2nd from the left)

I've recently replaced the spark plugs, and cleaned the jets/carbs out two years ago.

What else should I be looking at?

Re: 79 CB650 Running only on 3 Cylinders

Posted: Sat Jul 08, 2017 3:56 pm
by jcasey007
I assume you have checked you have a spark on number 2?

then check for vacuum leak on number 2 carb to start with if not a split carb to head rubber, do a compression test on #2

Re: 79 CB650 Running only on 3 Cylinders

Posted: Sun Jul 09, 2017 8:32 am
by MEHall
Easiest to start with is the ignition, check the sparkplug and the wires. Next is to check if you get fuel into that cylinder, that is a bit more difficult but not impossible. :wink:






8)

Re: 79 CB650 Running only on 3 Cylinders

Posted: Sun Jul 09, 2017 7:23 pm
by Folsoml
Carbs clean two years ago? Has it run since then?