Carbs synched but something's off

[BillyRok]

I synched the carbs yesterday but something is not quite right so I'm looking for some help. The valves are in spec, battery is new with a good charge (12.4v across the terminals, bike not running), coils read 3.2 ohms primary (a bit high as spec is 2.5) and 11k secondary, voltage at the coils is now 11.4v (bike not running) after cleaning some connections again.

Here's a quick 20 second video so you can see and hear what I have.

https://www.youtube.com/watch?v=-p2U0LlNfk0

But here are pics of a couple of the plugs, they all look about the same.
[IMG][/IMG]

[IMG][/IMG]

I started with the mixture screws about 2 1/2 turns out, ended up about 3 turns out when finished. These are the same plugs I was running last fall when I first tried the synch so they may be sooty from back then. I set the float heights (both sides) to spec when I cleaned the carbs but have not checked the levels with some clear tubing. Is it possible that the synch and mixture is good but fuel levels still high? Do I just need to get the bike out on the road at 4-5k and recheck the plugs? Can the plugs be cleaned (how?) or should I put new ones in?

It's supposed to be in the 50's this week so I hope to ride it to the dealership and get it inspected. Thanks for your thoughts.

[motoman]

Looks like its got a weak spark down in the lower revs. Need to find where that over 1.5V is leaking the all important smoke to the coils. (Ignition before fueling)

[MPittma100]

Sync

When you say "something is not quite right", what are you referring too exactly? If it is the plugs in the pictures, they are showing too rich. You need to clean these plugs or buy new ones and run the test.

What fuel mileage are you getting?

[BA80]

Change those plugs, put in some new ones. That should make a big difference.

I'm a believer in adjusting mixture screws individually per cylinder. You are doing these adjustments with the YICS eliminator installed correct?

[BillyRok]

Mike yes I was referring to the color of the plugs, was concerned that it appears to be running rich even though I think I have the mixture screws adjusted properly. I'll put new ones in and take it for a spin to check color. As far as mpg goes, I used to get over 40 but the bike hasn't been on the road since Oct 2011 so not sure if that is still a good bench mark. Could float height still be an issue?

Greg I have the YICS eliminator installed, gonna leave it in there. Screws were adjusted one at a time, watching the carbtune and listening for slight increase in rpms. Will get some new plugs, too.

Motoman, here are instructions you had given me last fall to check coil voltage

Key on, voltage at battery on pos/neg. term. for a base. Key still on, ground of meter to the three grounding wires/screw on voltage regulater hold down(this uses actual frame grounds as rest of sysyem does instead of from battery). Positive meter lead to each of the red/white stripe wire of coil plug-ins under tank(with key still on). Report the voltage first on battery(for a base voltage), then at those coil wire plug-ins for comparison(with key still on).

Dumb question perhaps, but are these readings to be taken with the key simply on or with the bike running? I took them with the key on but the bike NOT running...wrong way to do it? Last fall I had 12.2v at the battery on 10.6v at the coils. Then more info from you...

Lot of areas prone to voltage drops............cruddy contacts at ignition switch is biggest one. Mine on my 81 caused a drop to 9.5v @ the coils. At this point, just have removed the switches front protective cover where wires go in and unloaded a can of pressurized electrical cleaner on a straw up in there while flippin' key on and off having lots of crud and I'm sure any lubricant wash out.. Likely gonna have to remove switch and clean correctly to find one volt of all important still missing smoke. Think there's a tip with pics for removal and dissasembly, cleaning and re-assembly. Someone else will chime in I'm sure, and give ya' the link. I would follow it for correct operation once re-enstalled as there's some little springs that will manage to hide from you in man-cave crevisis upon disasembly along with getting fork-lock function correctly.

I cleaned the ignition and kill switches last fall, was still stuck at 10.6v at the coils. The other day I cleaned the dielectric grease out of the coil connectors and the connector in the headlight bucket where the wires from the fuse block go. Also ran a ground wire from ground at r/r to neg battery ground at the frame and voltage rose to 11.4v, one volt less than the 12.4v I see at the battery, again the bike is not running.

If the voltage at the coils is supposed to be checked with the key on and bike not running, then I'm losing 1v someplace...would welcome any thoughts as to where. If the voltage check is supposed to be done while the bike is running then I'll have to put new plugs in first and then fire it up and check voltage. Please let me know which way the test should be performed. Appreciate it.

[BA80]

The one and only time I used a carbtune tool like in your vid, according to it everything was good but the bike ran like crap. When I got home I hooked up my cheepo Chinese regular gauges up and it was WAYYYYY off.

Adjusted it with my gauges and it was good again. Try T-ing all the lines together to a single vacuum source and see if they all read the same.

FYI......adjust the mixture screws to the highest vacuum readings individually, resync, repeat............it may take several passes to get where there are no more adjustments needed.

[motoman]

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.

[BA80]

NOT running...wrong way to do it? Last fall I had 12.2v at the battery on 10.6v at the coils. Then more info from you...


I cleaned the ignition and kill switches last fall, was still stuck at 10.6v at the coils. The other day I cleaned the dielectric grease out of the coil connectors and the connector in the headlight bucket where the wires from the fuse block go. Also ran a ground wire from ground at r/r to neg battery ground at the frame and voltage rose to 11.4v, one volt less than the 12.4v I see at the battery, again the bike is not running.

Are you testing BOTH the battery and coil voltage WITH the key on?

[BillyRok]

Yes Greg, I was checking both with the key turned on but had not started the bike. Is this the right or wrong way to check? Is the bike supposed to be running or not?

Motoman, my issue is that I don't know/understand how to track this down. Not sure of the path to follow back from the red/white coil wires to the battery or what/how specifically to check for along the way.

Anything anyone can offer to help educate me in this process is greatly appreciated and I apologize in advance for my ignorance.

[BA80]

Yes, that is correct. I am not as familiar with the XJ as some on here but I can say that the voltage is being lost somewhere in a switch or connector. My money would be on either the connector to the ignition switch or in the fuse panel. Although the best way to trace the circuit would be with a wiring diagram.

I personally don't think the voltage drop issue is where the running problem is but it does need to be addressed.

[skids]

Well, if you are running rich, the problem is "at what range". These carbs should be tuned from high throttle settings - to middle settings - to low settings, in that order.

[wjw11teen]

Well, if you are running rich, the problem is "at what range". These carbs should be tuned from high throttle settings - to middle settings - to low settings, in that order.

how do i do this sequence

[BA80]

The problem being those are old plugs and the bike hasn't been ridden, just started, for a while so there isn't any real way of telling if it's rich, lean, or otherwise. No way of really tuning it properly without some saddle time.

[TopCatGr58]

Hey there Billy,

As the others have said, it would be good to track down the missing voltage, but the Xj coils run on the 12 volts all the time, they are not reduced by a ballast resistor, so the 11.4 volts isn't that low and shouldn't be causing this level of poor performance....IMHO!

So...I'll play devil's advocate: You say you cleaned your carbs LAST YEAR when you first tried to synch them? I can't remember any previous threads/posts regarding your carb cleaning...so we have to ask how well did you clean them...and did you use a KIT which might have come with replacement JETS? The K&L kits and their jets(pilot circuit) are known for improper sizing which is too rich!!

Also, the bike hasn't been run since 2011...possible for rings to have gotten stuck and haven't worked loose yet?? JAT.

T.C.

[motoman]

See you were maybe questioning float levels. Done with gasket off or in place? If done with them off, fuel levels will be a bit too high. Measured from 'gasket surface' means exactly that, which is 23mm.
Bike leveled(have to put a 1/2" piece under right-side of centerstand), and idleing, that setting will have fuel levels at the '3mm down from top of carb casting', which will be the top of a bowel bolts lock washer.

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.