Oh No!! I've got a big problem!

[prometheus578]

"I'm drooling with anticipation"

(Hhmm... maybe that's why women don't go on second dates with me)

[fxrer]

Inquiring minds want to know!

Shawn,

It's been a couple of weeks; did you ever figure it out?

Some of us are anxious to learn!

[Shawn27530]

Boat anchor out XS Motor In.

I took the boat anchor out yesterday, cleaned the frame and engine up and installed the XS motor in there. I had to put the XJ oil pan on the XS motor because the oil press sending unit is in the oil pan on the XJ. I did this so it would be a plug n play operation. But now I have a huge oil leak from around the pan, as I thought I could get away using the old gasket, Wrong!

The good news is the 79 motor makes a full revolution and puts out 160 psi on each cylinder with #4 being 162 ish.

Now that I have the Xj motor out I can, bust it down easier, I am now soaking the studs to get the barrels off. When I pulled the oil pan I didn't see anything out of the ordinary and (what little I could see of it) the primary chain looks intact. I will try to get the barrells off and check the pistons etc and see whats up.

Now are there any differences in the jetting sizes from the XJ to XS Carbs, I have both and I could run either set, after cleaning of course. Except if I run the XS carbs I would have to do away with my choke lever and cable which is fine with me, cause I like the lever on the carbs anyway.

[The Dutchy]

Hi, barely new to this forum, I recall working on the XS1100SF with gear trouble. On mine the small spring on the arm pushing and pulling the rod for the shifter fork was broken. Replaced it and thought it was cured. Found out later when I shifted it into first gear it was actually in first and thirds. One of the circlips on the gearshaft was not in place (groove) so gave freeplay to one of the sprockets. Got that one replaced and worked fine after that. Funny though if it was in two gears you could turn the main crankshaft about 3/4 turn before it got stuck.

Raymond.

[prometheus578]

"Out of the mouth of babes..."

Well, not babes, but the new guy. Hhmmm... without rereading the last 5 pages...sounds like he's hit on something that we may have overlooked. We did discuss tranny... but not the actual cause that would display that symptom, I believe.
I too have been waiting patiently, Shawn... but I know how other projects build up quickly and change priorities.
But those are YOUR priorities, not MINE. I want answers, NOW!

(Prom cries and throws food from his highchair!)

[GNEPIG]

.. sounds to me like the "new guy" has nailed the problem right on the head
..all hail THE NEW GUY!!

[mro]

Shawn27530

I pulled the clutch basket, and now the transmission spins freely by putting the bike in gear and turning the rear wheel. But still the engine won't budge

don't think it's the tranny



mro

[prometheus578]

"Why'd ja have ta ruin it for me, huh, huh?"

Ernest Borgnine as E. "Trucker" Cobb (Flight of the Phoenix)

Hhmmm... Guess we'll still have to wait fer the answer.
Sorry MRO, seems my memory's not what it used to be.
"Stop Dave... my mind is going... I can feel it... I can feel it."
HAL9000 (2001)
(All this useless movie trivia... I don't know how I function!)

[Shawn27530]

Which Carbs should I run??

Now are there any differences in the jetting sizes from the XJ to XS Carbs, I have both and I could run either set, after cleaning of course. Except if I run the XS carbs I would have to do away with my choke lever and cable which is fine with me, cause I like the lever on the carbs anyway.

[TopCatGr58]

Potato....Potahtoe!!

Hey Shawn,

The differences are in the carbs, but not too much for the engines theyare on! The 79 carbs are more adjustable so you can tweek them more for performance characteristics, like being able to change the vacuum slide needle position. The XJ's can't! The jetting is different, but due to carb internals difference, not the engine they are on! The 79's floats are easier to adjust cause you adjust them from the bottom with the bowl off. The XJ's are "designed" to be adjusted using the clear fuel hose connected to the bowl, carbs upright, and seeing where the level hits, then take the bowls back off, and adjust, repeat....P.I.T.A.

The presence of absence of the YICS circuit won't be a problem, so you could use either set! Just keep the sizing of the jets in accordance with the style of carbs. Don't go trying to put 137.5 mains in the XJ's carbs!!
T.C.

[Shawn27530]

XS11 Carbs it is then

Thanks for the info TopCat,

I will run the XS11 Carbs then. I am planning on running the Mac 4 into 2 I am planning to keep the original air box. Any recommendation of where to start with the jetting?

And if I decide to go with pods later on?

[fxrer]

Shawn,

On the left column, go to Tech Tips>Maintenance>Carburetors>Jet Sizes-Factory info. You'll see a chart with the carb specifications, jets sizes, etc for each model. That's good place to start.

For an XJ, the specs are: Main = 112.5 ; Pilot =47.5; Starter jet = 25; Main air= 140; Pilot air =170 Hitachi-BS34

There are also many, many threads on the subject of rejetting with pods, aftermarket exhausts, etc. Do a search, and you'll be astonished at all the information

[TopCatGr58]

Hey Shawn,

You may NOT need to rejet at all!? You will need to rig up a set of vent lines for the 79 bowl vents, don't just cap them off!
Then put in a new set of plugs, and check their appearance after a bit of riding! See how it performs, if you have good response thru the RPM range in all gears! Then check the plugs, and if they look too lean, remember don't go by the color of the insulator, but the color of the metal rim on the bottom of the plug.

And you might be able to adjust any mild leanness with a bit of tweaking of the floats! But with aftermarket pipes, you would only be looking 1 or 2 sizes up from the stock 137.5, so either 140 or 142.5 would be where you would be going!
T.C.

[mro]

hey Shawn27530

XS motor
XJ head
XS cams
Stock air box
after market exhaust
79 XS carbs


and you want jets too

larger valves with longer duration cams? & new exhaust??

better call prom



mro

[Shawn27530]

No, I decided not to swap the XJ head on, So basically I am just running a 79 XS engine and Carbs in the XJ.