1976 CB750K Field find!!!!

[bigdaddy84]

so I got this bike from a farmer who actually knows bikes. Ive known him for awhile and he takes care of them. The only issue I am having is that it had cobweb city going on. My question is when I use the kickstart on it I am getting compression out both exhaust but it isnt turning over. Kill switch is on the run position. So what in the world could be the issue? I have ordered a new key ignition since someone tried to steal it out my back yard and didnt notice that I locked it from under the forks (nifty little spot). I hear it is rare to have both coils go out on you and the PO said that he ran it last year before he winterized it. Which I can say he did cause it had absolutley no fluids in it till I added them. I will be adding pics of it but all the electrical looks good and clean, headlight works. so lets hear the ideas.

[cdaiscool]

You need 3 things to start a motor: compression, spark, fuel.

Do you have spark? Pull 2 plugs, 1 from each coil. Ground against your case, try starting (DON'T HOLD THE SPARK PLUG). See spark? Bright or dull? Weak spark won't do anything.

Do those plugs smell like gas? Look black from oil?

Do a compression check if you have the tools. Compression out the exhaust doesn't mean squat. You want 100 psi or more on a compression check. Engines won't run without 100 psi minimum - you want to be in the 140's on these bikes iirc.

Download the FSM at the top of the home page and go through its troubleshooting tips. Good luck, and we require pictures! It makes us happy seeing bikes.

[bigdaddy84]

so just pulled the spark on the left side if sitting on bike. put against the crank case and no spark. they are black and have gas on them so that is were I sit now. Other issue I am thinking is maybe bad coils? or just bad plugs? I dont know when the last time the plugs were changed and they look like they are in rough shape. I just cant figure out how to get to the 2 and 3 plug

[bigdaddy84]

file:///C:/Documents%20and%20Settings/Owner/My%20Documents/Downloads/FB_IMG_13715218571060335.jpg

[bigdaddy84]

how would I check for bad coils?

[motogrady]

you need an ohmmeter .  check for continuity, you should get a reading
on both sides of the coil.  I'm sure there's a number they should be, that's manual info.
no reading, broken wire.

if you were messing with the ignition switch,
and all of a sudden nothing,
and the only thing you changed.........

what really helps me is one of those 12volt electric probe lights, the pointy ones
that you can stick in a wire and it lights up if there's juice.
When you turn the switch to "on" one of the terminals on the coil show show juice.
switch off, or kill witch on, no juice.

clip the probe to a good ground on the frame or the neg side of the battery,
and go 'lectric huntin.