Cooler Cylinder

Hi to all
I'm a new user after being introduced by someone on our uk kwaks forum. I wonder if you could help me with this problem.
I have a 1984 GPZ 1100 A2 Unitrak with fuel injection. I have one cylinder which seems to run cooler than the rest being pot 1. Ive changed all the leads have decent plugs ( pot 1 is sparking ok) changed the oil, air filter, plug caps, and have used injector cleaner. kawasaki, here say that it is unlikely to be a blocked injector. The bike has only 23000 mls on the clock and its condition suggests it's been well looked after.Kawasaki say it could be low compression on one cylinder and if theres more than 10 psi difference with the others it wont fire on that pot. Therefore, would it be better if I converted it to carbs instead of dfi and how would i go about doing it. Or am i wottying about nothing. Help!!!!!!!!!!!!!!

First step for me at least would be a Compression test, need spec's, and if the dfi is working I would leave it be.
Carbs are good but fuel injection is great. haven't ever worked on a gpz1100 but you might look into having the injectors flow tested.

Or just moving one of the injectors that is on a good cyl. to pot 1 and seeing if the problem is still in the same location or if it moved to the other pot you put the injector from pot 1 into, if so replace that injector.

I'm going to get myself a tester, have been told it should be 125 plus. Mechanics not my speciality but dont mind getting my hands dirty + the shitty uk weather doesn't help. Have a fear it will cost a fortune to get sorted. i love the machine and don't want to part with it.
Cheers
ray

When you test the compression, open the throttle wide open.

I am curious as to how you determined the cylinder was running cooler? When was the last you adjusted the valve clearance? Many times, in these situations, the problem is ignition related. Once you have verified you have a problem, look to trouble shooting the problem and fixing it yourself.

You might consider contacting Lorcan ( www.750turbo.com ), he is a member here, lives in the UK, and is very familiar with the GPz's injection systems :)

When I start the bike, the exhaust pipes on the other three pots are much hotter to the touch. Ive not a enclue how to do the valves, though I do know it has shims. I recently replaced the r cover gaskit as the cam plugs needed replacing. The gaskit was lead and was about 40 uk pounds. I presume they fall to pieces when the covers removed.

Kawasaki quoted 250 uk pounds each for replacement injectors. Local breakers has good shelved set 60 all in so have bitten the bullet and ordered them. He also asked if it was pot 1 and had it been standing, which it had been in a garage for a year, on its side stand. I'm hoping it's the injector thats the problem now.

This situation is calling for a diagnostic but I bet either the injector's not squirting or the plug is not firing. I would be amazed that in 1984 the EFI could detect a 10 psi difference in compression from one cylinder to another (did it have a knock sensor ?) but maybe the software was that sophisticated even back then in the era of the Apple IIe and IBM Peanut.

Not only could you have a spitting injector instead of a spraying injector, you might have a vacuum leak there too. Maybe, just maybe.

Those 1100's are very desireable in the drag racing crowds here. Bet it's a nice ride!!!

Ive now changed the injector and theres no difference, and the plug is sparking ok. I'm going to get the valves adjusted next costing £120 aprox. As long as the cooler cylinder wont harm the engine, i'll live with it.
As for the ride. Well, I'm only 5ft 5 and 10 stone so its a bit heavy to move round the yard etc, but on the move it's a beauty. Have traveled from Manchester where I now live to my old London town with no bother. Bike is now rare here so have decided to keep hold of it. New exhaust system comes next.

I would still check the compression. This is always a baseline troubleshooting step. An inexpensive compression gauge is one that has a rubber tip that press fits into the spark plug opening. You just turn the engine over with all plugs removed and throttle wide open. The gauge will peak up and show pounds per square inches of pressure. This will tell you if you have ring problems or hanging valves once you have taken the measurement especially if you repeat the test with a few drops of oil in each cylinder. ONLY do one cylinder at a time else the oil will shoot up all over your ceiling. In any case, about a teaspoon of oil in the cylinder will seal the rings if they are a source of compression leak and compression will jump up greatly. You can also get a "leak down" test which is done with air pressure. The source of air leaking will pin point any compression loss but this should be done only after a normal compression test.

Once you have determined there is no compression issues, you should follow with the valve adjustment. I personally would invest in a shop manual and do the adjustment myself. This is a routine maintenance item and while it is tedious, it is simple to do and the only cost will be a supply of shims and a shim tool in the event your bike's shims are above bucket and not below.

Contact www.z1enterprises.com about parts. I believe they ship overseas and the owner, who lives in New York, is a Brit. He speaks Brit decently bwhahaha The parts might just be less expensive even though shipping might be a tad more.

Contact Lorcan, as he is technically astute and has a very informative web site. He knows FI and will probably be a better source of information re your bike than will be a local Kawasaki dealership.

A little F.Y.I., 10 Stone is about 140 pounds:
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