76 KZ900

Experimenting with different products to clean engine and covers before removing from frame.
Before and after 

Perhaps that should say after and before 

Was hoping no one noticed that lol

Which product did you like best.

I think any cleaner that won’t harm the aluminum will work it’s the scotch pad and nylon brush that does the hard work along with WD40.

Still having problem on 4th cylinder. Did another compression check with same results as before. Did leak down test and all cylinders less than 10% leak down, 4th cylinder had least amount. Switched plug wires and plugs same result. When starting cold after sitting couple of days, no smoke out tailpipe. Stuck clear hose in 4th carb bowl and fuel level went to joint where bowl meets carb body. When first starting pipe all cylinder fire and all exhaust pipes get hot pretty evenly, after 2-3 minutes of idling shutting off check as it warms up 4th cylinder pipe starts to cool off. When riding it I noticed whenever throttle is open more than half way regardless of rpm or gear it clears up and pulls strong. I’m thinking float level is too high, anyone agree?

Check the valve lash. When the engine heats up, valves like to expant and the valve clearance can go to near zero.
Some rust or carbon build up on the valve seat surface and seat rings in the cyl. head can make a lot of trouble!
A cheap USB Handy bore scope can help to give you some more internal view to the piston dom, cylinder bore and valve condition.

Torqued cam cap bolts to check valve clearances, can’t get my smallest feeler (.038) in between shim and cam on cylinder I’m having an issue with, maybe I found the problem. Thanks Scirocco 

Loosened valve clearance on trouble cylinder and no change. Replaced choke plunger with one from another carb no change. Rode about 15 miles, it’s only missing at small throttle opening regardless of RPM, when opening throttle beyond 1/3 to half throttle it pulls strong even from low (2000) RPM. Decided to do a running compression test. Hot engine open throttle I have 150 lbs of cranking pressure, added teaspoon of 50 weight oil jumped to 160. Started engine and gauge goes to 30 at 1500 RPM blip throttle to 2500-3 k RPM jumps up to 60-70 lbs. I’m thinking intake problem ? Excess carbon on intake valve or seat? Feedback appreciated. No smoke out exhaust noticed.

Have it mostly stepped down, engine out. Wheels and suspension later this week then off to sandblaster/ powder coater.

How do the rubber manifolds between carbs and head look?  Mine had some hairline cracks, barely visible.  Z1E has them.

Scotty

mvent wrote:

Loosened valve clearance on trouble cylinder and no change. Replaced choke plunger with one from another carb no change. Rode about 15 miles, it’s only missing at small throttle opening regardless of RPM, when opening throttle beyond 1/3 to half throttle it pulls strong even from low (2000) RPM. Decided to do a running compression test. Hot engine open throttle I have 150 lbs of cranking pressure, added teaspoon of 50 weight oil jumped to 160. Started engine and gauge goes to 30 at 1500 RPM blip throttle to 2500-3 k RPM jumps up to 60-70 lbs. I’m thinking intake problem ? Excess carbon on intake valve or seat? Feedback appreciated. No smoke out exhaust noticed.

I think it's unlikely to be a carbon build up issue, how old are the plugs and HT leads? Is the ignition advancer moving freely? What condition are the intake rubbers in (as already mentioned)? Are the pilot circuits in the carbs clean?