The bowls are the same as late model XS so a good one went on in the mangled bustard's place.
Did the synch "on the bench" using thin slice of light under the butterflies eyeball method, from previous experience that is all that's needed, 'specially since the YICS connects the 4 intakes. I don't plan on putting that rod back in. But might try it as an experiment one day.
You made me look!
not accurate information...they have extrapolated those numbers based on the 1978/79 model years..yes they all say the XJ1100 has 95 hp..they're all wrong...especially with the emissions controls with the YICS system it robs hp ..thats why most people leave the tool in there..
#9  
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| The transmission and its gearing is identical. The engine is very very similar. Not sure of compression numbers, but then almost every year of the XS engine had slightly different numbers for overall performance. Different cams, different pistons in 80-81, timing changes. Etc.. The biggest difference from the XS series engines to the XJ was the YICS system. The XJ has the YICS which basically is a way to equalize engine vacuum across all four cylinders. The biggest hassle is the need to block off the ports to properly synch the carbs. Most folks by the YICS eliminator and leave it installed permanently. Eliminating the YICS system. The engine will bolt straight up into an XS frame, the same carbs, exhaust, U-joint, etc will all bolt right up. The XJ has an oil level light instead of an oil pressure switch. IT also has the clutch and side stand safety switches. The XJ uses a vacuum sensor to signal the TCI of engine vacuum and the vac advance is built into the TCI. So you will want to pull the timing assembly off your F engine and put it in the XJ, so it continues to place nice with your TCI. The XJ being a one year model those TCI are harder to come by. From a performance reference, the F was a stronger engine than the XJ. more powerful timing setup, stronger cams, head, piston combo. The 80's models got detuned a little for EPA purposes. However, I still believe that most of us will never use the full capabilities of these machines enough to notice. __________________ Life is what happens while your planning everything else! When your work speaks for itself, don't interrupt. 81 XS1100 Special - Humpty Dumpty 80 XS1100 Special - Project Resurrection Previously owned 93 GSX600F 80 XS1100 Special - Ruby 81 XS1100 Special 81 CB750 C 80 CB750 C 78 XS750 |
Interesting, but not sure it's true.This discussion says the XJ engine was detuned due to EPA emissions..Scroll down to TC and Jerry's comments...No way was it 95 hp...but they dont say what the actual hp rating was...
http://www.xs11.com/forum/showthread.php?t=21283
and further discussion...
#9
10-31-2013, 10:52 PM
DGXSER 
Doctor of XSology(Deceased)Join Date: Nov 2008
Location: Cincinnati, Ohio
Posts: 9,769The transmission and its gearing is identical. The engine is very very similar. Not sure of compression numbers, but then almost every year of the XS engine had slightly different numbers for overall performance. Different cams, different pistons in 80-81, timing changes. Etc..
The biggest difference from the XS series engines to the XJ was the YICS system. The XJ has the YICS which basically is a way to equalize engine vacuum across all four cylinders. The biggest hassle is the need to block off the ports to properly synch the carbs. Most folks by the YICS eliminator and leave it installed permanently. Eliminating the YICS system.
The engine will bolt straight up into an XS frame, the same carbs, exhaust, U-joint, etc will all bolt right up. The XJ has an oil level light instead of an oil pressure switch. IT also has the clutch and side stand safety switches.
The XJ uses a vacuum sensor to signal the TCI of engine vacuum and the vac advance is built into the TCI. So you will want to pull the timing assembly off your F engine and put it in the XJ, so it continues to place nice with your TCI. The XJ being a one year model those TCI are harder to come by.
From a performance reference, the F was a stronger engine than the XJ. more powerful timing setup, stronger cams, head, piston combo. The 80's models got detuned a little for EPA purposes. However, I still believe that most of us will never use the full capabilities of these machines enough to notice.
__________________
Life is what happens while your planning everything else!
When your work speaks for itself, don't interrupt.
81 XS1100 Special - Humpty Dumpty
80 XS1100 Special - Project Resurrection
Previously owned
93 GSX600F
80 XS1100 Special - Ruby
81 XS1100 Special
81 CB750 C
80 CB750 C
78 XS750
In the 5 model years Yamaha made the XS/XJ1100..they actually lost money. because they never broke..They were over engineered for their time..This was before manufacturers learned of "planned obsolescence"...Glad to hear you have it sorted out..well done...part of me still wants it..
. That’s awesome!
Yes, that was me. There are pictures of it on the XS11 site someplace.
Do the fluids leak up?
