Confused

The float in the second moves freely when I take the bowl off, could it be getting stuck when I put the bowl back on? Could that prevent it from getting gas through to the cylinder?
Ed

It sounds to me that a thorough carb cleaning is in order here. #1 was leaking out the overflow, and by tapping, it was stopped. #2 is not firing by what seems like excess fuel.
You also stated that you had brown gas out the bottom of #2 bowl. Have you checked your tank for rust?
The other thing is, you said the vacuum petcock leaks and you installed a secondary on/off valve. Did you plug the vacuum line? I'm thinking that being the petcock is in need of repair (wore out), you may be sucking air through the vacuum line which might cause changes in idle.???

The vacuum from the petcock is hooked to the carbs, so it shouldn't have a vacuum leak. Yeah I guess I'll take 'em down and clean them over the weekend, order new jets and pods for it. I've heard up one size for pods, and another source says up two, which should I go with? I've cleaned the carbs before, and didn't notice any sizes on the jets, they may be worn off does anyone know what the stock jet size for this is?
Thanks,
Ed

1979 KZ 650D I believe... SR 650.

Post edited by: CptEDIV, at: 2008/02/01 12:38

Most 650's run the standard 102.5 main jet, but in 78 or 79 some bikes got the 97.5 for emmissions. WG says the 102.5's will work ok on these emmission bikes. Is your bike stock? I run a Kerker 4/1, stock air box with K&N filter and run 105's. Bike pulls like a bear all the way to redline +. But every bike is a little different. And yes, as rdgrnr says... sounds like a good cleaning, rebuild kits and adjustment is in order.

Post edited by: Bluemeanie, at: 2008/02/01 12:53

Aren't rebuild kits usually just new jets? So would I just put in 105 main jets with the pods, and then get other jets stock? I'll probably just get a new OEM petcock.
Then clean the carbs, put it all together and cross my fingers?
I want to order it all at once and do it right... So I'm trying to be extra cautious about it, even though I'm pretty ready to ride.
Thanks,
Ed

CptEDIV, well my bike runs great with the 105's but like I said, every bike is different. Different pipes, diff level of baffles, compression, diff ignition systems, etc. Pods can be very difficult to jet properly I've heard. Your bike may like 105's, 107'5's 110's or so. So I can't say 105's are for you. Heck, my bike might run even stronger with bigger jets! My plug color looks great so I'm staying where I am. You can ask all 650 owners (except badkaw of course!) what combination of mods and jets they are running. As far as the carb kits go, there is more than just jets, see pic below. Plus, if run the pump carbs, the bowl gasket in the kit does not have the provision for the accelerator pump squirter channels and will have to be ordered seperatly. Plus the kits come with "pilot" screws and you may be using "air" screws so will have to reuse yours. As far as OEM fuel (vaccuum) petcocks go, they made them up until 2005 for the KZ1000P (Police) so they are available for about $80.00.



Post edited by: Bluemeanie, at: 2008/02/01 13:28

Post edited by: Bluemeanie, at: 2008/02/01 13:32

Here are the "pump" bowl gaskets you will need, see the difference?



Post edited by: Bluemeanie, at: 2008/02/01 13:35

Sorry, wrong pic. Here is the right one...

CptEDIV wrote:

Put the new plug in with full choke. Started it and then killed the choke and it idled at 1.5 RPM. Its still not firing on the second cylinder....

Recommend determining whether fuel mixture is getting into the #2 cylinder combustion chamber.

Here's how -- As reported above, repeat cranking it up again and let engine run for a minute after getting off choke. Shut off the engine and immediately remove #2 spark plug and smell it and inspect it to detect any raw fuel lingering on the tip. Presence of unburned fuel would indicate fuel is getting there but failing to ignite. If plug is completely dry and free of any unburned fuel, it would indicate that no fuel is getting there.

While the #2 sparkplug is out, would re-check compression psi in #2 cylinder. Also be aware that satisfactory cold compression psi does NOT necessarily prove satisfactory compression exists at running temperature. A too tight valve clearance in #2 could seal okay when cool, but begin leaking and causing loss of compression as the engine warms.

I would recommend first getting it running satisfactorily with the existing jets, air intake, and exhaust system, before likely complicating things by making hit-or-miss changes.

As first suggested, recommend determining whether fuel mixture is getting into the #2 cylinder combustion chamber. If not, then changing jets, installing pods and a different exhaust system, probably won't make much difference, as fuel still won't be getting into the #2 cylinder combustion chamber. And if fuel mixture is getting into the #2 cylinder combustion chamber but not burning, such changes still won't make much difference.

Suspected problem areas may be better diagnosed when it is known whether or not fuel mixture is getting into the #2 cylinder combustion chamber. (See first sentence :lol: ).

Good Luck with however you decide to proceed!

Post edited by: Patton, at: 2008/02/01 14:30

CptEDIV wrote:

The vacuum from the petcock is hooked to the carbs, so it shouldn't have a vacuum leak.

Which carb? And does the vacuum line attach to a nipple on the carb holder, and run from the nipple to the petcock?

As the petcock vacuum feature is not being used, perhaps should cap off both carb nipple and petcock vac nipple. Which eliminates the vac line as possible source of problem.

Mainly wondering if petcock vac line runs to #2 carb.

Post edited by: Patton, at: 2008/02/01 14:44

Yeah, Vacuum from petcock goes to the second carb. I got em capped off, then I tried running it and checking the plug... It was dry and brand new lookin still.

So I found another post about a similar problem, where someone had just moved the carb over to the left so that the 3rd carb goes to the second cylinder. I tried that, and ran it, sprayed the exhaust and sure enough, it was firing. So that means it would have to be the second carb? I got the carbs off and am working on cleaning 'em now.

Should I have it put all the way together and ride able before trying pods and new jets? I have a real hard time with my airbox and air ducts... I was hoping clean them, rejet then put it all together with the pods to avoid having to take the carbs off and apart again, not to mention my airbox looks and functions like crap.
What do you think?
Thanks a ton, this site has been incredibly helpful.
-Ed

CptEDIV wrote:

Yeah, Vacuum from petcock goes to the second carb. I got em capped off, then I tried running it and checking the plug... It was dry and brand new lookin still. So I found another post about a similar problem, where someone had just moved the carb over to the left so that the 3rd carb goes to the second cylinder. I tried that, and ran it, sprayed the exhaust and sure enough, it was firing. So that means it would have to be the second carb? I got the carbs off and am working on cleaning 'em now. Should I have it put all the way together and ride able before trying pods and new jets? I have a real hard time with my airbox and air ducts... I was hoping clean them, rejet then put it all together with the pods to avoid having to take the carbs off and apart again, not to mention my airbox looks and functions like crap. What do you think? Thanks a ton, this site has been incredibly helpful. -Ed

Thanks for the report indicating problem in #2 carb.
If reasonably sure about best jet sizes for pods and 4/1 exhaust, grin and go for it! :woohoo:


Special attention to #2 carb --

Assure float-needle-seat is not clogged and preventing fuel from entering float bowl.

Assure float is not set so low that it immediately closes the float/needle interface and keeps fuel level way too low. Use the clear plastic tube test.

New pilot jet will resolve any clog in old pilot jet. Assure pilot circuit fuel passageway is clear from pilot jet on through pilot outlet orifice in bottom of carb bore.

Let us know if more detail is needed with regard to cleaning the pilot circuit air and fuel passages.