Can't sync the carbs...

[Zenuwlijer]

Check your electrical connections. Make sure everything got plugged back in properly. See if you're getting fire to the spark plugs.

I haven't touched anything which is connected to the coils.

I'll draw out one of the sparkplugs.

 

[Fire-medic]

The vent hoses. They go to the sides of the OEM airbox. There is that small L-bracket where each side's pair of hoses plug-into the L-bracket. This owner thinks he knows-better than the the factory engineers. I would look to restore them to their original length (hoses) and positions. This is a Morley's Muscle airbox lid, you see the double vent hoses and the OEM bracket.

 

[Parminio]

If memory serves the '85 didn't have the connections on the airbox for the vent tubes, they were just secured to the frame. I would guess (and I am guessing) that those carbs are not from the original '85, that they came off some other year model and they just cut the vent tubes off rather than run them over to the frame and zip tie them.

 

[Zenuwlijer]

The vent hoses.

I routed them properly as far as I know. The bike won't start with the airbox taken off either.

 

[Parminio]

The bike won't start with the airbox taken off either.

That's odd.

 

[Zenuwlijer]

See if you're getting fire to the spark plugs.

Heard of it, never done it.

Turn the ignition and the sparkplug against the block? If so, what part?

 

[Parminio]

You should be able to turn it over and see the spark plug firing. I always pull a plug on the right side of the engine, leave it plugged in, crouch down so I can see it clearly and hit the start switch. If you don't see it sparking between the center electrode and ground electrode, you're not getting fire.

 

[dannymax]

Rest the threaded part of the spark plug to a bare metal part on the engine.

 

[Fire-medic]

If memory serves the '85 didn't have the connections on the airbox for the vent tubes, they were just secured to the frame. I would guess (and I am guessing) that those carbs are not from the original '85, that they came off some other year model and they just cut the vent tubes off rather than run them over to the frame and zip tie them.

I checked the fiche, and it shows parts #54 and 55, the L-brackets for the float bowl vent hoses, on the 1985 parts inventory.



I suspect that you can run entirely-without the float bowl vent hoses, but the engineers put them in for a purpose. They could save $ by not-designing that as part of the carburetion venting system. But, there they are. I suspect their main purpose is at higher rpm and speed, they allow the float bowl to draw evenly. I recall when the ZX-11 was released, that type of float chamber venting was required because of the ram-air system which it used, to allow proper operation of the carburetors, the float bowl also needed to be pressurized above the level of gas for the carburetors to be fed properly at speeds when the ram air was functional.

 

[maleko89]

With the vent hoses, location is important. With stage 7 filter pods, you can remove them. But, when I added velocity stacks, it ran better when I put them back and positioned the ends near the air flow.

Mark

 

[patate657]

If memory serves the '85 didn't have the connections on the airbox for the vent tubes, they were just secured to the frame. I would guess (and I am guessing) that those carbs are not from the original '85, that they came off some other year model and they just cut the vent tubes off rather than run them over to the frame and zip tie them.

Do you guys think that it would be better for gas mileage to have it set up like the later models?

 

[Zenuwlijer]

View attachment PXL_20210719_132402139.mp4
I've got spark, so tried to start it again.

 

[Parminio]

Do you guys think that it would be better for gas mileage to have it set up like the later models?

As long as they can vent without the risk of anything getting into the tubes and back down into the fuel bowl it shouldn't really matter.

The whole idea behind running them to the filter box was that so any fuel vapor that escapes gets burnt through the engine rather than just venting into the atmosphere.

I wouldn't think it would make any real difference in mileage.

 

[Zenuwlijer]

Now what?

Reduce idle speed, or first try again with airbox?

 

[Zenuwlijer]

Oh yeah... It shut off by it self.

 

[maleko89]

A stock/bike w/o the airbox will run very badly. My '89 would barely start. The only time I was successful was with air correctors inserted in the main air jets.

 

[Parminio]

To me that means it's either running out of gas or flooding. If it doesn't start right back up, it's probably flooding. Are you running the choke at all?

My bike ran perfectly normal sans the airbox. Not sure why people have problems with that.

 

[Zenuwlijer]

If it doesn't start right back up, it's probably flooding.

This.

What to do now?

(And no chocke was used, but normally I would.)

 

[Fire-medic]

Yes, I'm in-agreement with maleko89 where the airbox is required to properly-run. That's also been my experience. I can get it to start, but it runs much-better with the airbox and lid secured, especially when trying to see about it running at increased revs.

Replace the airbox and lid, and if you removed the Y-piece of the lid, replace it. Then try to start it.

Have you ever tried using the flat palm of your hand, to 'choke-out' an engine, to see if it runs better? You lay the hand across the carb venturi (the airhorn/top of the carburetor) and then rev the engine. Often the 'hand-choke' will cause it to rev better, a sign that you need to replace the air filter for the induction system to operate as it's jetted. You may also find that one cyl in particular which isn't firing, will 'kick-in,' helping you to diagnose a problem with that particular cyl.

 

[V-Four]

My "Guess" is: it's either too much fuel now, or not enough. I wouldn't mess with anything but the carbs now.

Does it smell of more fuel than usual?
Does it usually start with the "choke" on all the way? IFSO, Maybe try without choke.

Maybe try with no "choke".

Maybe try with throttle slightly cracked open.


I think this is just due to all the readjusting of the throttle plates/idle, and once synced back to normal, your starting issue will be fixed.

Don't get discouraged. and make sure you have a charger nearby, as you may drain the batt in the meantime.. which might make you want to throw the whole thing in the river.


Stick with it. Take breaks as needed.



T$