2 CYLINDERS RUNNING HOT - 2 ARE NOT 1981 KZ1000J

Hey there me again. I typed out the whole description yesterday but forgot to send lol. I finally got the bike fired up and running smoothly after 20 years of sitting and overhaul. Cylinders #1 and #2 got HOT, around 500 degrees before I shut it down. #3 and #4 were running about 200 +/-. I'm assuming there is rust in the muffler/silencer. I'm headed out to see if the outlet flow is consistent on both sides. I would disconnect and run the engine but I have been told that is not a good ideas as the engine requires back pressure while running. Any ideas on how to clean the insides or how to remove the guts for cleaning ? Thanks in advance and hope everyone has a safe, healthy and happy New Year, jon

Cold cylinders are more likely to be related to carb problems than exhaust. What leads you to think the exhaust is plugged up?

I bet the exhaust system isn't plugged. I would install new spark plug wires or at the least redo all of the connections. the plug wires unscrew from the stock coils by unscrewing the ribbed compression boots. redoing those connections is how I solved an intermittent firing problem on #1 & #2, and I have since installed new Dyna ignition coils & spark plug wire set.



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Hey Nessism, I started the bike again today to check the exhaust output on both pipes. The left one was flowing very well (that's the side that got so hot at the engine end). On the right one, the flow was significantly lower. What kind of temperatures should I be seeing at the pipes where they leave the cylinder heads ? The carbs have been rebuild, new plugs but old wires. I did have a decent spark on all. Thanks for your reply and I hope you can point me in the right direction as new mufflers are not cheap lol

Have you check the balance/sync of the carbs after your rebuild/cleaning?

The only thing that will affect exhaust gas temp is the fuel air mixture. If the spark is sufficient to ignite the fuel air mixture it will burn at what ever tempreture that mixture dictates. Therefore I suspect the carbs are not set up correctly and are running lean on the hot cylinders.
With the engine warm and ticking over only the airscrew or float height should cause a lean mixture. So check those first. Use a colourtune for the airscrew and the wet method for the float height.

Now I'm educated in color tune. I ordered one but won't be here until the end of the month. I assume "wet testing is checking the float level with a clear tube ??? Keep the ideas coming lol. Will it make a difference whether the air box and filter are installed ?

Yes it will, air box and filter installed will restrict the airflow and reduce the air to fuel ratio resulting in enrichening the mixture.
Wet method aka clear tube method. All carb adjustments must be done with all the carburation related items you intend to run with installed.

OK fellow Kawasaki owners, Just a quick update. I checked my carbs again they looked good EXCEPT #1 float needle was upside down. I'm an idiot lol. I attempted to install the old rubber air box to carb boots and it just isn't happening. They're to stiff so I ordered new ones and they will be here Saturday for install on Sunday. I haven't attempted to run as everyone said to make sure everything is hooked up. I'm quite sure the float needle was allowing excessive fuel into the engine and that's part of the reason #1 and #2 pipes were so hot. Last time I did run it and I checked the outlet of the exhaust pipes I was very surprised that the #1 and #2 pipe had great flow but the other side was much less. I'll update after another test run but want to thank everyone that responded. Be well, jon

OK fellow riders, I installed the new air box to carb boots, filter and cover. The engine starts occasionally but will only stay running for 30 seconds. I have great spark and when it runs the choke has to be on at least 1/2 way. I have tried adjusting the pilot screws without much success. I can't color tune unless it stays running. I believe I have carb issues but I have rebuilt them 2x, checked the float level per the FSM. Here are my questions.
1) What should the pilot screws be set at for the initial starting point ?
2) Where should I go to have the carbs professionally rebuilt and what should I expect to pay ? (I'm willing to send them to someone on this website who can help, I will pay someone).
3) The little bit it did run I still have #1 and #2 exhaust at a much higher temperature than #3 and #4 with more flow through the #1 and #2 side (left) than the other 2.
Help me out please lol. I live near Myrtle Beach if anyone is close by and has the urge to assist. Thanks in advance

Did you bench sync them?
Steve

Steve, Thanks for the fast reply. Explain what you mean by Bench Sync. please