Join Date: Sep 2006
Location: Austin, Texas, USA
It definitely will FIT. I have a '93 1100 engine in mine, and I'm not exactly sure of the vintage of the transmission (I know it's K11).
The problem comes with using the '85 fuel injection with the 4 valve engine. I adapted the whole Motronic system from the '93. Next problem was adapting the '85 electrical system to run the Motonic. Not a job for a beginner and you have to make compromises as to what you really want to work. I remember I gave up the clutch interlock, there may have been more, but right now I don't remember.
After some teething pains (grounds mainly) the bike is totally reliable.
'17 R1200RS, 2 yrs. 27,000 mi.
'16 R1200RS, 18 mo. 28,000 mi. (gone)
'03 R1100S Boxer Cup Replika 6/200
'85 K100/1100RS, 34 yrs. 326,000 mi.
'05 R1200ST, 8 yrs. 57,400 mi.-3rd deer killed it.
'11 R1200RT, 2 yrs. 30,000 mi. (gone)
'99 R1100S, 2 yrs. 15,000 mi. (gone)
'96 Ducati 900SS/SP, 12 yrs. (gone)
500,000+ BMW miles