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Can't be right, it's a 4 cylinder motorcycle, should be 4 numbers hopefully all close together but not likely to be all the same. Compression test is a relative test and in a perfect world you (or the manufacturer) would have recorded the original compression numbers from when the engine was new to compare with.
 

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1982 kz440a
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Discussion Starter · #46 ·
Can't be right, it's a 4 cylinder motorcycle, should be 4 numbers hopefully all close together but not likely to be all the same. Compression test is a relative test and in a perfect world you (or the manufacturer) would have recorded the original compression numbers from when the engine was new to compare with.
The compression on the dead cylinder is 155
 

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Discussion Starter · #47 ·
Well I got the new ignition switch installed:
Wheel Vehicle Car Automotive lighting Motor vehicle

The label is upside down:
Automotive tire Motor vehicle Rim Automotive wheel system Gas

I attempted to pop of the shroud so I could rotate it 180degrees, but it would not go easily and I didn't want to break the plastic so who cares. ...

While I was waiting for the switch to come in I was using this:
Circuit component Composite material Electrical wiring Wire Cable

It's wireless:
Car alarm Communication Device Everyday carry Gesture Thumb

It has two channels (two spst relays):
Passive circuit component Circuit component Hardware programmer Electronic engineering Electronic component

You can program them for latching, toggle, or momentary. I wired it so "A" controlled ignition and "B" for parking lights. Another setup i tried was channel "B" set for momentary to control starter switch. It was pretty cool setup for wireless start. I don't know what I'll do with it now. I could wire it parallel and use it in conjuction with the keyed switch but I will probably forget and leave the ignition on one day... maybe I'll use it for some LED'S on a future flip..

Anyways, none of this matters when the bike is only running on 3/4's cylinders. I'm going to take a nap
 

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The compression on the dead cylinder is 155
Yes but if they are all 155 you are good to go, and if the others are higher that will point to a problem on the low one. If it is just a little lower then that supports the possibility of just being a clearance adjustment and that would be a good thing.
Compression is within spec limit range to operate in theory, but not necessarily in practice.
 

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Discussion Starter · #49 ·
Alright! She's running on all four cylinders now! I think my gas was contaminated with water. Maybe I didn't get it all out after soldering the pinholes in the tank. Anyways I drained the tank and the bowls and the problem is solved. The next thing I need to adress is a rev hang at idle. With the idle set to 1k I blip the throttle and she hangs up at 3k and takes a very long time to return to idle. I'm gonna try turning the pilot screws out. Unfortunately this requires pulling the rack because it's next to impossible to get to the screws for 2 and 3 when the carbs are mounted.
 

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You need a hanging fuel supply or low pressure pump to tune the carbs. I had a used Honda cvcc pump for the gsxr's. Syncing the things is key to getting any real idle or acceleration. Hanging idle to me with these things sounds like you may have muffed up the carb reassembly after cleaning them. I found this was quite a common mistake with many people in the past. Take the caps off and make sure the bellows and the o ring are in the proper location. I liked to sync the carbs closest for a strong takeoff rpm not at a flat idle. Probably best to go with flat idle if you just want to be done. I miss the rumble of these beasts.
 

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All 4 cylinders sounds good, so many guys with 4-cylinder carb problems here lately it's difficult to remember what they look like. Water in fuel; didn't we talk about isopropyl alcohol aka gas line anti-freeze before? If you don't collect the water out of the lowest part of the float bowls the next best is to carry the water through the engine and that takes alcohol. It's not a fix but it is a fuel treatment.
 

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Carb slides can stick, usually because the engine has been run with a history of insufficient air filtration. CV carbs can stick for several reasons if that's what you have.
 

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Discussion Starter · #53 ·
Yes. They are cv carbs. All of my bikes will probably be cv carbs because I buy bikes that people are practically giving away due to "carb problems"

I inspected the diaphragms when I replaced the needles last Friday. They are in good condition. No tears or pinholes. Soft and pliable. The slides are working correctly after reassembly, Verified by blowing in the port and observing them rise and fall consistently.

I have the pilot screws 5 turns out and the rev hang is improved but not completely eliminated. I would no longer call it a "hang" more like a "mildly sluggish return to idle" Its time to move up to a larger pilot jet. I supposed the aftermarket can that was crudely installed has changed the jetting requirements. She is only a brake job and turn signals away from being rideable now. Finally sat on her and rocked through all six gears in the driveway tonight. I'm getting excited now. So glad someone else gave up on this bike!
 

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Discussion Starter · #57 ·
How did the syncing go? This will change how the bike runs drastically for better or worse.
I synced them last week with the Morgan Carb-tune Pro. Since changes were made I can sync them again tonight (to be thorough) but I don't expect a carb-sync to fix a problem that is most likely caused by a lean condition on the pilot jet.
 

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See the extra plunger pump assembly on a typical #2 carb in a bank of CV carburetors:
Fuel tank Motor vehicle Vehicle Automotive lighting Automotive tire

My understanding is they put that diaphragm pump on there so the engine returns to idle better, it does it by enriching the fuel mix just slightly on deceleration.
... note the only carb that is different is #2, the rest are virtual parts interchangeable.

Point of this post is, look for something that looks like a fuel pump, study the linkage to determine if that pump is actuated on acceleration or deceleration at the linkage and then look for problems relating to that fuel circuit.
 

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Discussion Starter · #59 ·
See the extra plunger pump assembly on a typical #2 carb in a bank of CV carburetors:
View attachment 106993
My understanding is they put that diaphragm pump on there so the engine returns to idle better, it does it by enriching the fuel mix just slightly on deceleration.
... note the only carb that is different is #2, the rest are virtual parts interchangeable.

Point of this post is, look for something that looks like a fuel pump, study the linkage to determine if that pump is actuated on acceleration or deceleration at the linkage and then look for problems relating to that fuel circuit.
These are the mikuni bst36ss and there is no such provision. At idle the fuel is metered by the pilot jet and the pilot air jet. The mixture is partially discharged into the main bore out of the bypass ports and the remainder is metered by the pilot screw and sprayed into the main bore through the pilot output.

I flushed and bled the brakes then took the bike around the block today and I am satisfied with the motor, the transmission and the clutch. I think i did very well for the initial investment of $500

Tomorrow I will pull the wheels and inspect the bearings and drivetrain and replace a dry-rotted valve stem on the front tire. She's at least safe an reliable enough to ride to the bmv for a vin inspection during lunch. I can hardly wait to get her on the freeway and really knock the dust off!
 
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