Check compression on donor motor

Hey guys, i just bought a '80 kz750 4 cylinder to put in my cafe project. I want to check the compression before i begin the swap. How would i go about hooking up a battery to the starter to turn the engine over - while it's out of the frame?

Thanks!!

Well, you could just hook a battery up to the engine and sarter. I would just turn it by hand to cycle it. However, I think it's supposed to be done when warm :whistle:

There should be a fat cable from the starter motor that goes to the starter solenoid --- that would be pos (+). Then you could use jumper cables --- clamp pos (+) to the starter cable. clamp the neg (-) jumper cable to the engine. Then connect the jumper cables to a battery to check the compression --- you could use a car battery. connect pos to pos then neg to neg. It probably doesn't matter, but I would do it with the car engine off.

PS: remove all 4 spark plugs beforehand.

You also need to hold the throttle wide open, or remove the carburetors.

Also, the cylinder walls might be dry, so I would put a little oil in the cylinders & turn the crankshaft by hand beforehand. maybe let the oil soak overnight. snowmobile fogging oil would be handy. remove the right side engine cover & use a 17mm wrench an the big nut (not the smaller/inner timing advancer bolt).