[1fast4door]

Update 2, I am pretty sure its intake gaskets/o-rings if I spray the base of the intake the idle comes right up. There are also small cracks around were the bolts go on the out side intake, no idle change when sprayed, is this a concern? I will throw up pics later.

George

[1fast4door]

Here are the pics of the intake cracks



With the o-rings being this wet on dis-assembly I am fairly confident that this is the problem, anyone wanna make me feel better and second my opinion.


Oh yeah and I think I found the oil leak...

[1fast4door]

Well I am still chasing this issue, I installed the new o-rings and it seemed better but it is not fixed. I still have a vacuum leak some where. I do have a couple questions though. How much vacuum should I see at idle? or what is a good number if all was proper? and how much should I be able to adjust the idle with the thumb screw? What should I see as a max RPM if the bike was running properly?

George

[Rare83Kat]

If the idle thumb screw is screwed all the way in to the point of coil binding its spring and it still isn't in contact with the carb linkage as you showed in your pictures...then you have to have at least one throttle blade closed so far that it is holding the linkage open so far that its not touching the idle adjusting stop screw.

Fix that issue and re sync the carb set. Start by opening up the throttle plates on numbers one, two and four. The linkage should move now into contact with the adjuster and you can unscrew it a couple turns. Then re sync the bank.

When that's fixed you should easily be able to adjust the idle down.

hth

[Kreylyn]

Did you replace those boots with new, or just the orings?

The picture of the one boot looked to me like replacement would have been needed.

Krey

[1fast4door]

Rare83Kat, the thumb screw does contact the throttle before coil bind, It just doesn't seem to open the butterflies as much as it should, but at this point I don't think that is the problem. I had gone over to a buddies house, old school bike guy, and after looking everything over he wanted me to ask what I should be seeing for vacuum at idle and at sync RPM, and how much RPM I should actually get out of the adjuster screw. We looked at a set of CBX carbs he had and the throttle plates opened way wider then my set, and then we started his ZX and off of the choke the idle adjuster would raise his RPM to 5000 or so. I realize that this is apples and oranges and far from scientific but we both were curious.

Krey, I did just replace the o-rings, and was redy to just throw some more cash at it and buy the boots, but the reason I went over to my buddies was to test the set I have. I made a plate that I could bolt the boots to and then we made a PVC plug that we could apply vacuum to and they all held 15 inches of vacuum, so I am guessing there good. If you see a flaw in the testing, I would like to hear it. I do really appreciate all the help and tips to trying to figure this out.

Now I am going to try either tonight or tomorrow to get the bike back together and see if any thing has changed. This past weekend I went through the cabs for the third time and did a longer soak of the carb bodies, but was not able to put it together and test before Wednesday when my friend looked everything over, I will keep you guys posted and thanks for the help.

George

[Kreylyn]

Rare83Kat, the thumb screw does contact the throttle before coil bind, It just doesn't seem to open the butterflies as much as it should, but at this point I don't think that is the problem. I had gone over to a buddies house, old school bike guy, and after looking everything over he wanted me to ask what I should be seeing for vacuum at idle and at sync RPM, and how much RPM I should actually get out of the adjuster screw. We looked at a set of CBX carbs he had and the throttle plates opened way wider then my set, and then we started his ZX and off of the choke the idle adjuster would raise his RPM to 5000 or so. I realize that this is apples and oranges and far from scientific but we both were curious.

Krey, I did just replace the o-rings, and was redy to just throw some more cash at it and buy the boots, but the reason I went over to my buddies was to test the set I have. I made a plate that I could bolt the boots to and then we made a PVC plug that we could apply vacuum to and they all held 15 inches of vacuum, so I am guessing there good. If you see a flaw in the testing, I would like to hear it. I do really appreciate all the help and tips to trying to figure this out.

Now I am going to try either tonight or tomorrow to get the bike back together and see if any thing has changed. This past weekend I went through the cabs for the third time and did a longer soak of the carb bodies, but was not able to put it together and test before Wednesday when my friend looked everything over, I will keep you guys posted and thanks for the help.

George

There isn't a "vacuum" psi or reading to give that you would measure from the carb sync ports for example. This is what you would do instead....

Vacuum is created by the engine. If you question the engine is working properly in creatting the vacuum, then do a compression test and leak down test on all 4 cylinders. This will point towards issues that would cause a decrease in vacuum from the engine turning over (bad rings, bad valve seats, etc...).

If the engine checks out, then at that point all you do is "sync" the carbs... basically adjust the throttle plates so that vacuum each carb has at the sync port is the same. Again, that specific value isn't relevant, as long as they are all equal.

Krey