KZ550 compression test

Hey everyone. After putting my KZ550 together for the first time since the last owner took it apart I've noticed a few problems. When I turned it over for the first time last week the engine turned over immediately. I rode it around for a couple miles and the engine power seemed to be cutting in and out. At first the engine would stall at 1/4 throttle and then come back on when I released it. After turning the idle screw in more the bike would run pretty decently and I could turn the throttle as far as I wanted without killing the bike. Now I'm trying to start the bike and the starter motor is going but the engine won't turn over without holding the throttle wide open. Once it's finally on the engine is cutting out at 1/4 throttle again and the idle adjustment knob isn't helping. I never did a compression test on the engine because it did turn over and figured it had enough compression to run so it wasn't worth testing. I feel like I've gone through everything else and I have no clue what the problem is. I bought a compression tester earlier today at Sears and the adapter wasn't the right size and they don't have another set at my store. Can anyone tell me where I can find a good compression tester kit that will fit an 81 KZ550. Also if anyone has any other suggestions as to other things that could cause the problem it would be greatly appreciated.
Thanks
Nick

What size did your sears tool come with? 14mm? I think you need 12mm. Lots of testers out there. Harbor Freight sells one, but I had one read about 20psi low. They do come with the adapters though. You could grab one from them, use the adapter with each gauge and see how it reads for you. Remember a warmed up engine, with the throttle held wide open, a fully charged battery.
As for reasons why it is acting up, I would say carbs. Did you clean your fuel tank? Install an in-line filter for a gravity feed system? Probably got junk in the low speed pilot/ transition circuits. Also make sure the wet fuel level is correct with the clear tube test. Re check for vacuum leaks.

I'm not sure the of the size of the adapter because I don't have the packaging anymore, however the tool was designed for cars so the adapter it has was too big to fit into the sparkplug hole. A friend of mine had the same problem with his compression tester from harbor freight so I stayed away from that one. Can you tell me what needs to be unplugged to do a compression test? I know there's a fuse or wire that needs to come out but my Clymer manual says just screw the reader in and turn the bike over. I took apart my carbs completely and sprayed each piece in carb cleaner and blew compressed air over all the pieces and inside the circuits. I installed a new inline fuel filter when I was putting the bike together a couple weeks ago so it should still be good. When I got the bike I put gas in the tank and sloshed it around and emptied it into a container to look for rust or dirt inside of it. It appeared to be clean. There aren't any vacuum leaks in the carb boots or air box boots. I tested my fuel level earlier and it looks like the level is a bit high, however I was using a smaller tube than the 1/4 inch tube the Clymer manual suggests. Not sure if that makes a difference.

Won't be a fuse to undo as then you won't have the start button. Easiest thing is leave all the switchs off. Just use the Solenoid, either jump the two big battery posts with a solid metal object like a socket extension. Or un-plug the small wires, test which of the two has power when the key is on and the start button is pushed with clutch pulled in. One is power one is ground. Hook back up the ground one, then use a remote start button, or a jumper wire from battery positive to the wire that was hot, with it un-plugged. So ground stays connected, and the power wire is bypassed with your Hot wire/ start button. This way the starter works, but nothing is turned on. So battery stays up better, and there is no spark for a fire.
Clear tube test, it's just a sight gauge. Diameter of tube isn't a factor.

How are the choke flaps?

You can also just pull the small wires off the coils and crank the bike like normal.

They recommend bigger than 1/4" because capillary action will raise the level in gthe tube higher than the fuel level in the float bowl. I just use a small hose and jam it into the end of a bigger clear tube.

If you don't already have the factory manual, there are several in my signature, which you should probably keep.