Threaded injector ports on K100RS

[Carey J]

Morning all, can anyone enlighten a new brick owner as to why the injector ports are threaded and will readily take spark plugs.  Given the injectors simply plug in and do not require thread I was a little puzzled. I recall being told some time back (whether right or wrong) that the 84 K model was the first with fuel injection, not sure if that may have any connection or perhaps there has been a change in the injectors at some time. 

Cheers oh and a merry Christmas to all.....................carey johnson

[TimTyler]

Mine ain't threaded.

[Laitch]

Continuing with the juxtaposition theme, will the spark plug holes readily take O₂ sensors?

[K1300S]

Hmmmm.  I have never seen a fuel rail on a bmw threaded.

Post a pic!

[Elipten]

I think there is some confusion. My injector ports are not threaded

[Scott_]

I recall being told some time back (whether right or wrong) that the 84 K model was the first with fuel injection

Well that is true to the point that the K series engine was designed from the beginning for Fuel Injection(and water cooled to boot) as compared to the carborated twins of years prior.

[motodude]

Pictures might be helpful.

Tom

[Martin]

What year RS is it I have never seen threaded injectors ports on any K bikes. :dunno
Regards Martin

[Laitch]

They're like Easter eggs, Martin. You've got to look for them in the shrubbery. It's obvious they're out there—just maybe waaaaay out there. :hehehe

[TimTyler]

...  enlighten a new brick owner...

Did you buy two at once?

Your signature lists "84 K100RS - 85 K100RT "

[Carey J]

Good evening, not sure I understood some of the responses, had me doubting what I had seen so after several attempts at using a torch and I-Pad managed to get a snap of a port where you can see the thread outline, I also got a thin piece of wire and you can feel the slight movement as you drag it up or down.  I photographed the rail and injectors as well indicating they do not show any damage etc.  I own two k100's the 85RT has a chair and is being used by my son at this time so am unable to compare the ports bike to bike.  I have had the 85 since 2003 or 4 not sure now, the 84RS is a toy on the bench at this time and I have had it since 2004.  My preferred ride at this time is the 08R3 with the chair as I have a dog that will not let me get out the yard without her and she prefers the double seat of the rocket.  The RT has a DJP chair is narrow and uncomfortable for her.  I have had the head & valves etc done in a rebuild and the injectors cleaned etc and I would imagine if there was a problem someone with more savvy than me would have picked up an issue.  regards carey johnson

[Laitch]

Darn nice photograph, Carey! Thanks for coming through with that.

I don't see any threads but I can't stand back from the screen far enough to make these specs I'm wearing work right. The marks look more like heat impressions. If it were my bike, I'd just stuff the toe of a sock in there instead of a spark plug until I replaced the injector.

[K1300S]

Look like some machining marks below the area the injector seats in.  Nice purple rags! :-)

[Carey J]

Oops have realised the injector shot is upside down.  Never thought of the marks (thread) possibly being machine markings however all four are similar to one portrayed and that sounds a reasonable explanation.thank you all...............regards carey johnson