$300 for a yamaha xs 1100 Midnight Special Engine

[posthuman]

I found a yamaha xs 1100 Midnight Special Engine for $300

what parts are the same/ work on an '82 XJ1100 ?

carbs fit?

[John]

You can just drop it right in, and then change out the ignition pick up coils, and you may have to swap out the alternators. The XS and XJ use different alternators. You should be able to use your current carbs and not have to re jet. I had an XJ engine in my bike for years, and I was able to use my XS carbs without any changes.

[posthuman]

cool
for $300 I figure its good for parts?
or better yet i can bore, shave and cam it etc for a performance project

[trbig]

If you are thinking about using it for parts with your XS, just remember that the YICS ports will have to be addressed if just swapping the heads or something. I have the XJ head on my XS motor, but had plug off the ports on the head before I could.
As stated, the XJ is supposed to have a better charging system, so I would swap all that out and stick with the XJ alternator and such.
You can find motors cheaper than that.... one just went from a running low miles bike for 177 bucks on Ebay... but you have to account for shipping and/or pickup fees. If it's close enough to go pick up and the price is right for you... by all means... snatch it up!

Tod

[Fredjohny]

I put an 80-xs1100 into my xj, did not change my regulator and am using the xs alternator not the xj.....no problems yet ( 2yrs). The plug ins must be the same cause I did not cut any wires.

[Jerry]

If you swap engines into the XJ you chould change the TCI ignition box. The '81 engines already had the solid-state ignition (differnt TCI box, though.) so you don't have the mechanical advance mechanism to deal with. If you go back to the '78 - '80 models with mechanical advance, get the matching TCI box. The XJ uses a boost sensor in place of the mechanical advance, so some minor changes need to be done, such as taking the boost sensor off the XJ.

Other minor point is that the XJ carb bell size is 54mm instad of the XS 52mm, so your carb to airbox boots will be a bit loose when using early carbs on the XJ. Also, the XJ uses an oil level sensor rather than an oil pressure sensor. Don't know how this affects the XJ's instrument readout; maybe someone who has done the swap can address this?

Dropping in the $300 midnight engine should not be a problem, but there will be minor differences - XJ uses a cable activated choke instead of the manual linkage choke - but these can be overcome fairly easily. You should have the matching TCI...that seems to be the biggest issue to making the swap work OK.