problem with 1984 zn700 ltd

[bigshow]

hello, the problem is i can ride it around the block and feel the header #1and #2 are always the same temp #3and #4 are diffrent sometimes 4 is cooler than #3 sometimes its the other way around...lol i know its got me confused... what would cause this? its getting fire,fuel and air i havent done a compression check yet,,could it be the vavles ? thanks for any help

[RCW]

Given the age I would start with a complete valve adjustment and do a compression test once the valves are adjusted. If the compression is good, then install new spark plugs and check the rubber mounts to which the carburetors attach to the cylinder head to be sure they are not cracked and are properly tightened to the carburetors.

Then crank it up and see if it is running smoother and evenly firing on all cylinders.

I would not be surprised if the carburetors require work, as the diaphragms in that year are not compatible with the fuels we have now days, so are likely cracked which impacts the fuel feed rate of the main jet needle. The chokes on this model are real butterfly chokes triggered with a complex mechanical linkage, and that will need to be checked to assure all chokes are applying and releasing in unison.

[martin-csr]

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[RoadRunner322]

Put a bottle of strong fuel injector cleaner in it and run it through a tank. I'm sure the bike will run better afterwards but may not fix it completely. I have used Valvoline Complete Fuel System Cleaner in the past but it has disappeared from the shelves it seems. I think maybe the expensive Chevron Techron may be good.