Is this supposed to be there?!?

Hey guys,
Ok, in cleaning my carbs I found out:
1. My main jets aren't consistant.
Jet 1 & 3 - 118
Jet 2 & 4 - 120

Is this ok?

2. when I took the top cover off and undid the allen wrench cap that holds the needle valve and spring, I found that under every needle valve (between the base of the needle and cylinder that it goes in) was a hex nut.
Firstly, is that supposed to be there?
Secondly, the "clunk test" that I've read about...I've failed it.
Because the hex nut and the base of the needle bind up when the needle valve is raised.

Now, the bike runs better with the hex nuts in than it does with them out.
but it's still not running well. (no power in the low rpms and backfiring every once in a while.)

Any help would be greatly appreciated.
Thanks guys,
Wayne

 

Somebody with their nickname lettered across the front of a gray sweatshirt, Mickey Moused your Carbs.
I wouldn't be at all surprised if that nickname was "Goofy"

You're Carbs are presently F.U.B.A.R. "Yucked-up beyond all recognition"

I would be willing to bet BIG Money your Emulsion Tubes are Capital See, Elle, Oh, Gee, Gee, Eee, Dee ... Clogged.

You are running on Main Jet Output without benefit of Main Air Jetting.

Your bike might "Run" like that ... but, we BOTH Know it don't run the way you wanted it too or you wouldn't have dived-in to find the Disneyland Mods that are Jury-rigged to make the bike go.

Pull-off the Main Jets and Washers ...
Push-up ... from the Bottom ... the Brass Tube the Main Jets Screw into.
Screw a bolt matching the thread of the Jet into the Bottom of that Brass Tube and Drive it the heck out of there if it don't move easily!
Snap a picture of them in their present condition and we'll tell you where to go from there!

 

I actually came across a tech bulletin for HC and CO Specifications, dated 11/18/83 that states......

Pay special attention to the following carburetors during reassembly, they have main jets and/or jet needles which vary in size from one cylinder to another.

In the Main Jet list is......
XJ650LJ, LK - Cyl 1 & 4 127.5 Cyl 2 & 3 132.5

 

Different main jet sizes in a set of carbs is not that unusual.

My Vstar 1100's stock setup was a 110 main jet in the rear carb and a 112.5 jet in the front carb. Now that I'm running pod filters, it's got 142.5 mains in both carbs.

The varied jet sizes are another good reason to keep the parts from each carb separate from the other carbs when you take them down for a good cleaning.

 

My snowmobiles run different jets in the two carbs... a richer jet towards the pipe.... which also helps keep the motor running more consistantly during sizable altitude changes. (2 stroke motors being much more sensitive to quick altitude changes. In the mountains we can easily gain 3000 ft of elevation in a matter of minutes.)

I don't think this really applies to your bike... just thought I'd put it out there!

 

Raising the Needle Valves the width of a Hex Nut worries me. That seems to indicate that the Main Fuel Jet Flow is Restricted in some manner ... usually pointing right to the Nozzles (Emulsion Tubes)

That the Engine didn't Flood-out would further indicate that the Nozzles are all Clogged and the raising of the Needles meant to allow a greater flow from the Main Jets.

Not satisfied with the results from just raising the Needles a mile and a quarter, different from Stock Main Jets were substituted to help increase gas flow.

Get the Carbs knocked-down to Bare Body's ... Clean them like a Pro and assemble them with the right Jets and we'll have some fun getting it tweaked-up right so you can enjoy the Bike's full potential.

 

Richer jets go in the middle two carbs to help keep them cooler.

 

Ok guys,

So I opened them up again and this time I took the FU (hex nut) off of the BAR (needle valve).

I also removed the emultion tubes and here's what they look like:

http://xjbikes.com/coppermine/displayim ... =2465.html

I can see through the small holes on the sides just fine and other than some oxidation they don't look horrible.

What's next?

Thanks,
Wayne

 

Blow Carb Cleaner through the Main AIR Jet and see if the Passage to the Port where it blows into the Emulsion Tube Cylinder are clear and letting the Carb Cleaner blow Out in there.

Look at the Needles.
Are they all the same in length, circumference and taper?

 

Air/cleaner is moving through the main jets fine. also through the smaller jets.

All the needles are the same size, shape, taper.

Did I mention that it's only really running poorly at low RPMs?

 

Main AIR Jets. Not FUEL Jets.
Main AIR Passage.

You got to be able to Spray some Cleaner in the Main AIR Jet and have it come-out the Port where the Main AIR feed comes-in ... inside the Cylinder where those Emulsion Tubes came out-from.

Then, for your "Low-End" ... Blow-out the Pilot AIR Passage.
Blow the Cleaner in the Pilot FUEL Jet hole ... Blocking the Pilot Mixture hole with a finger.
Then, blow it in the Pilot AIR Jet ... Blocking the Pilot FUEL Jet Hole.
Then, release the Pilot FUEL Jet hole and block the Pilot Mixture Hole.

Flush it out ... BOTH Ways!

 

Gotcha.
Ok, I've mostly run out of carb cleaner for the night.
compressed air seems to be moving fine through both the air and fuel jets.
Although...maybe not enough movement?!?
I'll get some more carb cleaner tomorrow and really flush it out.
Also planning on getting some new spark plugs (again).
Also putting the larger jets on the 2 middle carbs. (?)
Thanks again Rick for all your help,
I'll get back to you tomorrow.

 

Ok,
This afternoon I blew cleaner through all of the air/fuel passages mentioned above. Things seem to be fine in all areas.

Now of course the bike won't start...as in dead battery won't start...except the battery has a full charge. I'm going to read up on starter and fuse stuff and try to figure that out.

(Revision) - After I looked for about 3 seconds in the haynes manual...I realized that I must not have had the bike in Neutral. I'm an idiot. Going to try again in a few minutes.

-Wayne

 

Senior moment?
Hope you found this problem...

 

ok guys,
I took her for a spin last night (maybe 15 minutes around the neighborhood) then took her out again today for about a half hour and let her cool off so I could check the spark plugs. Definate improvement. It still stalls out a little on takeoff but its not fouling plugs and it rides great. I'm going to keep tweaking the pilot screws, but I think I've weathered the worst of the "get a motorcycle and imeadiatly it won't run and you curse and scream and have to immeadiatly learn everything there is to know about it" storm.
Thanks for all the help Rick and everyone else.
now the fun begins. (making it run beautifully)
I'm certain I'll need all your help the whole way.
-Wayne
p.s. Tip to anyone reading: It turns out the carbs are REALLY REALLY important.