My fuel petcock started leaking after I cleaned my carbs too. Mine was due to sitting for awhile without fuel in the tank I imagine. I ordered one from eBay which for great and was cheap, but by leaving a bit of gas in the tank and sitting it over a bucket it miraculously stopped leaking on its own. I'm assuming something inside dried out and had to be relubed. I don't think being out of sync would cause that great of an increase to cause your leak. Hopefully someone can provide more insite.

 

thanks gtcole. I am going to test it off the bike by pulling on the hose to see if gas comes out / leaks. I have taken it apart before because gas was leaking out of the emergency valve on the bottom but after cleaning the gasket and stretching the spring a little everything worked fine. Maybe I will try to take it apart again, and i will probably do a sync anyway.

 

I tested the petcock off the bike by pulling on the vacuum and it seemed to function fine. The gas poured out, and then completely stopped after about 5 seconds. In the off position gas would not run even with a vacuum applied. There was no leaking, and I just tightened the screws to make sure nothing was coming undone. I am going to do a sync either tomorrow or over the weekend and then ill get back with the results.

 

Sounds good, also may be worth checking the fuel line if you havent already.

 

I synced the carbs and now my bike idles at 2k with the adjuster backed all the way out. Did I just screw something up or is there something I am missing.... It seemed to be idling fine while I was doing the sync.

 

Is there any chance that one or more of your slide pistons are sticking, and not returning to the lowest point of travel? Honestly, this really shouldn't cause an issue at idle anyway, but I'm just throwing something out there... I assume also that you have already investigated for any vacuum leaks, correct?

 

well when you say vacuum leaks, do you mean from the vacuum ports... or anywhere on the carbs? I am not really sure how to look for the leaks other than run my hand along and feel for a leak.

Some useful information may be that when I turn the choke on the idle drops dramatically and the bike either dies, or the idle slowly comes back up after a few seconds and sky rockets.

Also the tube going from my airbox to the center of the carbs has a little black box inline. That box has nothing inside of it and the clip to keep it together is broken so I just electrical taped it together. Is there supposed to be a filter in there? tht could be a leak right?

I just ordered a new petcock from china. Should be in in a month haha. Now I will finally have a reserve again and a filter inside the tank so i can get rid of my inline filter which may also clear up some fuel flow.

 

Well, if you're not running an F2 petcock, the only vacuum port that could affect you, would be the port off of cylinder 1, which is used for supplying vacuum to the petcock, so that fuel will flow when the engine is running.
If you don't have an F2 petcock with the vacuum diaphragm, then you need to make sure that port is plugged.

This is normal... when the engine is not up to full temp, the choke will cause it to idle fast, but relative to how well your fueling is sorted, once the bike is at full operating temperature, the choke should cause the engine to stumble, and/or die, when engaged.

No, that will not be a possible vacuum leak, those are just your carb vent lines, but yes, there is supposed to be a filtering element in the air-cleaner base, to filter the vented air, so tiny critters and debris cannot be drawn into the carbs.

The most common vacuum leak on these bikes, and the one you should be looking for, is around the carb boots, both where they are clamped to the carbs, and where they are clamped to the inlet tracts on the heads... if any of those 8 total clamps are loose, or any of the 4 boots are damaged, to the point they won't seal properly, that is where a vacuum leak will likely be.

The easiest way to check for this, is to start the motor, and get it just warmed up enough that it will idle without the choke, but still be somewhat cool externally, then spray some carb cleaner around the carb boots, to see if the idle obviously changes when you do so - this will help you find the leak, and is an indicator, because first, at the leaky spot, it's just drawing in extra air, then you introduce something flammable to that, and the idle will be affected.
Something flammable... this is why I advised to do this when the bike is just a little bit warmed up, to reduce the risk of fire, when spraying a touch of carb cleaner to find any leaks!

 

That cleared some things up for me thanks a lot JNSRacing!

I am running an f2 petcock with the vacuum line from cylinder 1. 3 and 4 are plugged, and 2 has an adapter on it but a little black plug/cover over top.

I was unaware of the choke situation. I was reading around and it appears that my situation can can happen from an air leak (lean mixture), but if it is normal than I will not look into it too deeply.

I will try to cut a piece of my aquarium filter pads and fit it into that box just for safe measures. Additionally my boots are not in the best shape. I have this problem where it seems the left 2 carbs are seating properly but than the right 2 carbs are a bit lifted on one side. And than when I try to push down the right carbs, the left carbs shift a bit. My old carbs did the same thing and I changed the boots exactly how they were so maybe it is just the boots and not the carbs or engine.

i will look into a new pair of those boots, its probably time that they are changed regardless of them leaking because they are starting to crack.

 

Yeah, any air leak will skew the way things should be in any given situation - all I was getting at with my comments on the choke, is that it will increase idle speed when the engine's cold, and will likely cause it to run rough and/or die when the engine's warm, when an engine is running normally. Until you find your air leak, if indeed there is one, I wouldn't worry about the choke, just use it as little as needed, for getting the bike warmed up, until you identify and fix your issue.
I have to ask, though, are you certain that the choke circuit is disengaging correctly, every time you close the lever? Obviously, a slightly hanging choke cable will cause a bit of a high idle, and could throw things off.

I would just get the proper part from your local dealer (17254-KAZ-000), it's not even $2.

If your boots are actually warped or have chunks missing, certainly replace them, as they are only $10 to $12 each, but one thing that can help with getting things seated, is to smear an eensy bit of grease on the inlet tracts on the head, and a little on all the surface of the boots that will make contact with those tracts, then use a heat gun to put some good heat into the boots, and quickly get the carbs on. Once you've got 'em started, just straddle the bike where the seat would be, and hold each end of the bank, rocking them a little, fore and aft, as you push down on them, then, if you think they're a touch off, use a rubber mallet to gently rap on the flat upper part of the carbs, where the air-cleaner base mounts. You can squat next to the side of the bike, and look across from one frame upper beam to the other, to eyeball whether or not the carbs are seated, as it will be obvious if each edge of the carb bank is or is not in the same positon, relative to the frame.

What I do, is get the cables connected, then flip the carb bank end-over-end, for smearing on the grease and heating the boots - don't worry about the grease keeping things loose, I have always used this method, and it has never been a problem, just be sure your boot clamps are nice and tight, and those carbs won't ever be going anywhere, until you want them off again.

By the way, if you don't have a heat gun, Harbor Freight regularly has the one I've used for years, on sale, for $9.99.