differences XS11 and XJ11

[nightpilot]

I have an XJ and just noticed the engine is different than my buddies 1980 XS. Does anybody know the differences between engines and bikes. Mine came with a fairing.

[CatatonicBug]

I believe the XJ used something called the YICS system. Not really familiar with it, but there are plenty of threads that talk about it, and even a tool for sale here that will eliminate it. Of course there are plenty of other differences between the XS and the XJ in general.

[Crazcnuk]

The motors are essentially the same. The YICS system is a method of balancing vacuum across the cylinders, supposedly to make them somewhat self-balancing.

The YICS system could be put on an XS, but no one seems to have seen any advantage to it.

The ignition systems are different, tranny the same, etc.

[Jerry]

If you use the Search function at the top of the screen and use differences xs xj you will get quite few hits that list the differences. One of them is
http://www.xs11.com/forum/showthread...ht=Differences
The XJ has some unique features, but there are differences between all the XS - XJ models, including differences in gauges, brake calipers, reat set (footpeg) placment, seats, ignition systems, and trim. There are differences between Standards and Specials of the same year as well as differences in the same model across years. Nothing major, but they do exist.

The main differences of the XJ are the YICS induction system (different head), brush-style alternator (higher output) LED gauge system, Special styling but with a larger fuel tank, square handlebars (adjustable for width and height) air adjustable suspension front and rear, and a more involved wiring system that includes side stand and in-gear interlocks. There are minor differences, such as the XJ's battery level sensor, brake fluid level sensors, linked braking system (back and front-left are tied together through the brake pedal, front right from the front master cylinder) and carb jetting differences.

If you look at parts lists, the first 3 letters/numbers incicate which model bike the part was first used on. Parts unique to the XJ begin with 10M. However, many parts are carried over from the first XS11 in '78. These include gaskets, transmission parts, final drive parts, and many other odds and ends.

Yamaha offered factory fairings both the XS and XJ; these were generally dealer-installed options. Vetter and others offered accessories as well. Main issue with the XJ is the fact that it was sold in the US for only 1 year, 1982, other markets (Mexico and Canada) for a couple more years. That makes getting some of the unique parts harder. For example, the XJ uses an oil level sensor instead of an oil pressure sensor; the XJ sensor has been discontinued by Yamaha.

There are quite a few XJ owners on this list, up from when I got active back in the late '90s. They are good bikes, but have idiosyncrasies that other XS 11 models don't have.

[madmax-im]

I too have an '82 XJ1100 Maxim...and until I joined this forum I never realized that the XJ was related to the XS...moreover I never understood the XS/XJ legacy either ...crazy 'cuz I've had my XJ since it was brand spankin' new I recently bought a "YICS Eliminator" tool and will be installing it to block off the YICS ports...another difference with the XJ motor vs. the XS motor is that the XJ's wer a bit detuned making less h.p...this was due in large part to the YICS system...I do believe.