Carbs synched but something's off

[mack]

XJ carbs

I'm sorry I just have to ask this. Are the XJ 1100 carbs CD or CV. You mentioned you have the YICS closed off so I was just wondering. The only XJ I've ever worked on was a 650 so I had to ask.

[Yahman]

The key is getting all four actual fuel levels the same. Precision and patience along with several float removals/install/measure to initially get all 8 floats identical height helps the fuel level results match up better. If you haven't already, after removing float pins, chuck them up in a drill and lightly touch a file(small flat-bastard) with side of file to GRADUALLY remove the raised shoulder above the pin head till pin just lightly drags going all the way in.
That'll save from having a broken post, as you may have them off several times getting things sorted.

I agree with motoman, get the floats right first, they are the foundation of a good synch. If the actual fuel levels are not the same, the carbs will not truly be synched the same. You will be compensating for the difference in fuel levels.

[Winterhawk]

Looking at the vacuum tubes during the sync it looks to me that the YCIS tool is not being used. This has nothing to do with the plug reading though.

I had 1 plug like that once, it ended up being the vacuum sync tube slipped down into the intake rubber. Took me forever to figure that one out.

BTW, there is not enough bounce in the mercury for having a YCIS tool installed during the sync. They should be bouncing more. IMHO

[BillyRok]

I love this site

I just gotta say, I just love it when a member can ask a question and by the next day several others have offered ideas to help...no wonder you can end up addicted to xs11.com!

Follow up to the questions/comments ---

TC I soaked the carbs in pine sol for about 36 hrs after taking them completely apart, did not separate the rack though, cleaned everything with carb cleaner and compressed air. Put in new needles/seats, mixture O-rings/washers, new Yamaha 47.5 pilots, and one new plastic float. The pilots had no holes in them so I asked everybody about that, this was the response...

That's Yamaha for ya! Yep, the XJ's pilots are no holed design, they changed the carbs a bit so the pilot circuit gets it's aeration separately, not directly thru the pilot jet, therefore no holes. Enjoy!

so I used those jets. Not sure about the rings being stuck.

Motoman I'm pretty sure I measured the float heights with the gaskets off. My FSM makes no mention of float heights, but says to check with 6mm clear tube connected to bowl drain...looking for 3mm plus or minus 1mm below the carb mixing chamber body. I say pretty sure because I posted here for clarification and got this response --

As to measuring the float height, first, you measure the height from the gasket flange but with the gasket removed. So remove the gasket, then measure from that surface to the highest part of the float like you were measuring.

Sounds like that was incorrect info and measurement needs to be taken with the gaskets in place? Can I use a torpedo level on the carb covers to check for carbs being level front to back and side to side when synching? I think I'll try that first with a piece of clear hose to see what the fuel levels are currently.

Mack my FSM says "model is equipped with four "constant Velocity" (CV) carburetors..."

Winterhawk yes I do have the YICS Eliminator tool installed, will leave it in there permanently.

Another question since I may have to pull the carbs again. Is there a trick to pulling the carbs on the XJ? I've read about guys pulling the carbs in 10 minutes but these are a real pain to get off!! Thanks

[crazy steve]

Another question since I may have to pull the carbs again. Is there a trick to pulling the carbs on the XJ? I've read about guys pulling the carbs in 10 minutes but these are a real pain to get off!! Thanks

Look here (use the Youtube version)...
http://www.xs11.com/forum/showthread.php?t=35349

This is a XS, but is more-or-less the same for the XJ. The XJ is a bit tougher because of the different airbox, but you just need to do a bit more fiddlin'...

[sparkfly88]

sorry for thread jack...but WAIT...you measure with the gasket on the carb??!!?!?!

I've always taken mine off...I thought 'gasket surface' meant the surface the gasket sat on....not the surface of the gasket

maybe thats why I'm running rich............

[BA80]

I've always measured with the gasket off. I believe that IS the way it's to be done. The manual says the gasket surface of THE CARBURETOR not the surface of the gasket.

Now, back to your regularly scheduled program.....................

[MPittma100]

No Gasket

+1 here. Float level is to be measured with the bowl gasket removed from the carburetor. Measurement is taken from the gasket surface of the carburetor housing.

If you set the float level with the gasket on the carburetor, you actually will be setting the float height (level) too low.

A lower than spec setting is not going to cause a rich condition. It would rather tend to cause a lean condition.

It is confusing to me that the bike is capable of 40 MPG with the plug looking rich as in the pictures.

Mike

[motoman]

+1 here. Float level is to be measured with the bowl gasket removed from the carburetor. Measurement is taken from the gasket surface of the carburetor housing.

If you set the float level with the gasket on the carburetor, you actually will be setting the float height (level) too low.

A lower than spec setting is not going to cause a rich condition. It would rather tend to cause a lean condition.

It is confusing to me that the bike is capable of 40 MPG with the plug looking rich as in the pictures.

Mike

Not being there hearing it run makes for some guessing of similar issues. From the plugs, my first inclination was low voltage TO the coils down in the lower revs., with voltages coming up at the 4K and above range. Was the issue with mine having a conbination of weak coils and some all important smoke ecaping from the kill switch.

[BillyRok]

Seems we have some difference of opinion here as to whether float height measurement is to be taken with the bowl gaskets on or off...certainly not trying to start something here but which is correct? Does it vary early vs late carbs? As I mentioned, my XJ manual makes absolutely no mention of float height, just a picture of the gas level in a clear piece of gas line connected to the bowl drain and held up next to the bottom of the carb where the bowl bolts on. Soooo, can anybody clear this up?

[BA80]

I don't have an XJ book but the carbs are the same as an 80 - 81 XS except for how the enricher is applied.

The clear tubing is how to check if your measured setting is working within specs. The measurement is done with the gasket removed, measuring from the carburetor gasket surface to the highest point (lowest point actually when upright). The gasket surface has a raised ridge running all the way around it for sealing purposes and to keep the gasket properly positioned. DO NOT MEASURE FROM IT. Measure from the flat surface.

[TopCatGr58]

Hey again Billy,

Like Greg said, NO GASKET, measure from the Gasket mating surface of the carb body. Secondly, Yamaha decided to make things even MORE difficult and so came up with the clear tubing float level measuring process!
Most folks just use the 80 specs, and set them to the 23 mm level, and then can tweak them depending on their performance, throttle response, mileage, plug appearance and such.

Okay, Good cleaning process...so no damage should have been done to the butterfly shaft seals, and you removed and replaced the Pilot jets with OEM, yes the XJ's are stated that they can use the holeless style! You didn't state it, but just want to be sure that you also removed the central emulsion tube called the MAIN JET Nozzle once you pulled the main jets? The other thing that wasn't mentioned was did you also remove the PILOT SCREWS from within the little sealed chambers on the top front of the carb bodies?? They are sealed in there by the factory but need to be removed so you can thoroughly clean the pilot circuit, put in new rubber orings onto the end of the pilot screws, and then adjust them for optimal tuning.

If you've already changed the oil/filter on the engine, then you'll just need to get it running, put several hundred miles on it, and then check the compression to see if it's near spec ~142 +/-10% at sea level. IF the oil/filter hasn't been recently changed, then you can put a few ounces of Mystery Marvel Oil in the oil, run the bike only on the centerstand for 10 minutes till normal temps, no hard throttles or high revs, don't put any real load on it or ride it. Then drain oil/change filter. MMO is very good as removing varnish/gum, stuck oil and therefore rings.

T.C.

[motoman]

When checking running fuel levels with engine warmed up and idling with no enricher, be sure and pinch that hose off at both ends tightly when removing after closing drain screw. A couple splashes of fuel on hot exhaust and heat shields raises the pucker factor. Would'nt wanna hear bout' a fire disaster!

[BA80]

Why would he be checking levels with the engine running Brant. It's done static.

[Brent]

missing smoke

Just have to track pri. ignition voltages back to where the drop initiates from. Sounds like some poor grounding issues attributed in part. Keep goin', you'll find the missing smoke.

I found a poor connection (missing smoke & voltage drop) in what appeared to be a tight factory crimp connection. Seemed tight, looked clean...but after 30 years & a slight tarnish...
Check large red wire coming off battery, Especially at end where it connects to Solenoid...AND smaller red or red & white ignition circuit wire that is joined to it at that crimp connection where it attaches to solenoid. Not sure if that is your problem, but it was sure easy for me to miss. Other spade connections in this circuit were even worse and easier to identify.

At lower RPMs, Stator makes much less power. Bike could misfire then, darken plugs and run better at higher RPMs. All carb recommendations here sound right, should be followed & checked. (I too need to reset my float heights). Do not be surprised to find that some/many "carburator" problems are electrical.

Hope you find those sneaky hidden electrical gremlins as well as needed adjustments, moving on to running right and happy motoring.
Good luck wrenching,