650csr H2 Fuel/Carb line routing??

Hey guys,

I recently bought an 82 Kz650csr not running. I think I've narrowed my not running issue to a pretty obvious problem with a less than obvious solution. I took the carbs off to inspect the insides and in doing so I found that multiple ports on the carbs simply did not have hoses on them.

After scouring for a conclusive diagram or a video at least showing something of a process where you can see how they’re routed, I’ve turned to you fine folks in hopes of getting something by the way of a visual to go off of.


Middle port was where the main fuel line went in. The two ports on the outside were left completely open. Cant imagine thats correct.



This is how the vaccuum lines were set up. Can anyone confirm if this is a functional set up? Seems strangely routed, to me anyhow.


The Y fitting the branches from the front to the petcock and vacuum port in the last photo.



Thanks in advance for any help.

The one other thing I noticed while trying to start the bike is that after cranking, the left two cylinders plugs are wet and the two on the right are dry. I figured it may be a fuel delivery issue,

There is no "breather" on the petcock. The petcock has a vacuum line that attaches to a carb. When the engine is running vacuum in the carb uses that line to open a diaphragm inside the petcock which then permits fuel to flow from the tank to the carbs. The 2 lower ports (between carbs 1&2 and 3&4) are vents; your bike may have tubes from them connected to a clean air system, otherwise the tubes should vent to the atmosphere. Take another look at the diagram and the text below it for more info. Ed

Ok yeah after looking again I must have selectively ignored the blue line portion. Well that's too bad that my obvious problem wasnt a problem at all haha...

In either case, the written portion seems to point to my vacuum ports being routed incorrectly.

The description is helpful but I'm really looking for a diagram or visual of the routing. Im pretty novice in this system and I'm having trouble getting a picture from the description.

Again though, thank you.

In the 1st photo, the exposed ports are the vents. attach tubing to them & route them so water doesn't get in.
On my 81 650-csr the vents are routed over the airbox shoulders and fitted snugly between the airbox & side covers. the left side has a frame clamp to keep the tubing in place. The 81 has VM24 carburetors but the airbox is the same.

Edit:
In the 3rd pic "1" & "2" should be connected to the vacuum ports on the #1 & #4 carbs.
The petcock vacuum tubing goes to the vac port on carb #2. the vac port on #3 is capped.
Assuming you have the stock vacuum petcock.

Oh I see! Well good know what is supposed to be done with them. I've seen a video of someone completely disassembling these carbs and in the beginning there's hoses off of them. Thats where I was getting led to believe they went somewhere more specific.

Thanks!

Edit to your edit lol

I think I can work with that! Hopefully the hose they used to connect those carbs are long enough to get to the petcock. I guess buying more wouldnt be a big deal.

Thanks again

If you need new tubing, the vac line is 1/4" & the fuel line is 5/16" ID. It's usually recommended to install an in-line fuel filter. some of the clear ones aren't fuel proof --- I think it's the ethanol that ruins them. I've been meaning to get an aluminum Russell fuel filter --- the element can be cleaned or replaced.

Is the stock clean-air system still fitted?

Good Fortune!

Yep stock air box is still fitted.

Looking at the description of how the vacuum lines are supposed to be routed then looking at mine, Im guessing this is why fuel wasnt getting to two of my cylinders.

I'm going to be antsy to get after it and check tomorrow.

If this logic is off please let me know.

Thanks everyone so far.

Be sure to route those vent tubes down to below the swingarm and away from the rear tire. If the carbs overflow because of a stuck float raw gas may flow from these tubes and you want to be sure to keep that gas off the rear tire.

You don't need any tubes on the float bowl drain nipples. Those are just there in case you want to manually drain the float bowls. On earlier year bikes those nipples were functioning over flow tubes but not on the later model year bikes.

Those four vacuum ports need to be sealed tight from external leaks. As mentioned you need to connect your petcock to one of them and also the air injection system needs a vacuum signal as well so I think that connects to another one, or use a T in the line running to your petcock.

BTW, you would be wise to check fuel level with the carbs off the bike before installing them. Getting the airbox boots all lined up is a pain and those carbs are prone to sticking float needles. Also, be sure to run a wire through the pilot jets if you haven't already done so. The orifice is super small and prone to clogging.

Good luck

Clean the carbs then hook them up.
Steve

Patton wrote: Is the stock clean-air system still fitted? . . . .

Not the air-box.

The clean-air system would probably look something like this:





One posted photo has tubes joined by a tee that may have been supplying vacuum from two nipples on the carb or carb holders via a tee to both the petcock and the clean air vac control valve (another tee).

When the clean air paraphernalia has been removed, any then unused vac nipples should be capped/plugged, because an open vac nipple will result in a huge air leak.

Good Fortune!

Ahhh yes, I see now.

Yes I believe all of that is still there. Not quite the same configuration as pictured here but I believe it has the one larg hose going to the air box and then the only other hose is what I have pictured above, the thisrd picture with the T hoses.

So my understanding as of now is I need to take those T'd hoses and connect them to both 1 & 4, then connect another directly to the petcock and the last one that doesnt go anywhere just needs to be capped, is that correct?