K 100 injectors

[Cgswssbmwk100]

i have been giving a run down in another thread, so I decided to stat a new one here


I just bought a K100 LT non runner.  ‘91 139,000 miles.  Tank cleaned, after market fuel pump.  Pulled plugs ( which required a 5/8” plug wrench) new OEM plugs on the way.  Problem remains will fire on starter fluid but not on gas.


I figure my next most likely thing is the injectors.  Of course I have to figure out how to get the side fairing off first, but I’m sure there is nothing tech about that, just finding all the bolts (and getting them loose).


While I see lots of different ways to clean injectors, I was thinking it might be best to just replace the injectors because I don’t know the history on this


Now checking Fleabay I see I have lists of choices.  Used stuff, new after market, rebuilt OEM, upgraded OEM w 4 hole, and of course new.


I’m thinking most about the new aftermarket and the upgraded 4 hole


So I’m sure there is a bunch of you that has gone with one of these 4 options.  Any really bad stuff about the new after market stuff?  I’m leaning to the rebuilt and improved 4 hole as even if I don’t really need new injectors, the claims for the 4 holes improvements sound good


I’m hopeing some of you that have tried these two options can give me some feed back


Thanks!


Craig

[Filmcamera]

I installed these a couple of months ago and have been very happy so far

https://www.ebay.com/itm/BEST-UPGRADE-Genuine-BOSCH-Fuel-Injector-Set-of-4-Update-4-Nozzle-Tip/281435347207?hash=item4186da9907:g:KjgAAOSwMg5ZXrPb&vxp=mtr

[billday]

Send them to these guys, you can't go wrong:

http://www.mrinjector.us/

[Martin]

Even just cleaning your OEM ones should give you a significant improvement. I cleaned mine and had a noticeable improvement. Depending on who you talk to you will get different opinions on 4 hole versus 2 hole. I've talked to a few injector guys and got different opinions. One guy said no benefit due to the fact that BMW designed the injectors to hit the back of the valves. Another one said 4 hole should give a finer spray better atomization. The only problem I can see is as Gryph brought up, smaller holes more chance of blockages. Really I don't believe you can go wrong with either injectors as long as they're clean. Running Techron once or twice a year also helps. I would really love to see a back to back dyno test of 1 hole versus 4 hole and then the matter would be settled.
Regards Martin.

[rbm]

... Of course I have to figure out how to get the side fairing off first, but I’m sure there is nothing tech about that, just finding all the bolts (and getting them loose).

See this page:  http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/k75rt.fairing/k75rt.fairing.htm

[Supershooter]

Mr Injector was a great when I was fixing my 85 RT, $17.50 per injectors plus a little frieght.


Supershooter

[Martin]

If you wish to know more about pintle hole numbers type in 4 hole versus 1 hole fuel injectors in your computer. There is a lot of information out there. And after reading more information, I have come to a conclusion that it really doesn't seem to matter. I believe that there is no real benefit to be gained to switching to the 4 hole type, and the benefits that can be felt are due to the fact that you are replacing dirty injectors with clean ones. There is also a possible psychological benefit that comes with more is better or bigger is better.  :dunno
Regards Martin.

[Laitch]

I’m hopeing some of you that have tried these two options can give me some feed back

Here are a few threads with feedback, Craig.

[jakgieger]

I like them...most likely psychological though .  I find myself upgrading lots of things (like led lights, internal diode alternators, radial tires :neener: , etc.) on my menagerie of older machines.  Not a huge change though.  I also had to do something as my bike had been idle for an extended time.

[Cgswssbmwk100]

Film camera, thank you for the link.  I’m confused.  They list a number of K100 models, but only list the K100 RS for 1991.  Do the K100 LT and K100 RS take the same fuel injector?  Some of the adds indicate all the K100 2 valve engines take the same injector, but it appears the 4 valve motors have a different injector


Also the link to the procedure the remove the faring was a great help.  I think to look inside the radio cover for bolts!  (Ok, I didn’t even know where the radio was)


Thanks! Craig

[wally.fisher]

Film camera, thank you for the link.  I’m confused.  They list a number of K100 models, but only list the K100 RS for 1991.  Do the K100 LT and K100 RS take the same fuel injector?  Some of the adds indicate all the K100 2 valve engines take the same injector, but it appears the 4 valve motors have a different injector


Also the link to the procedure the remove the faring was a great help.  I think to look inside the radio cover for bolts!  (Ok, I didn’t even know where the radio was)


Thanks! Craig

Have a search for tills.de, injector specialists who have a swap system, they are in Germany.


Sent from my iPad using Tapatalk

[Martin]

CGS you need to list the year of your Brick, I'm not sure whether you have a 2V or a 4V.
Regards Martin.

[rbm]

... Some of the adds indicate all the K100 2 valve engines take the same injector, but it appears the 4 valve motors have a different injector

Yes, all the 2V K-bikes take the same injector (bosch 0280-150-210 152cc @3 bar).  The 4V and 1100 K-bikes have Motronic instead of Jetronic EFI systems and need a higher flow rate in the fuel delivery (bosch 0280-150-705 164cc @3 bar).

[Cgswssbmwk100]

Thanks everyone!  I contacted the vendor and I guess there were a few years when the RS had the same 2 valve as the LT.  Of course, being new to the bricks, I didn’t realize that.


Martian, sorry about not putting the info in each post.  I’m also new to forums and tend to make errors.  I listed the year in the first post of this thread and thought that was OK.  I guess I should put it in the title from now on


Thanks again,
Craig

[Martin]

Craig how did you know I was an alien from Mars?? I came to Earth solely to abduct a Brick loved them so much that I decided to stay.  :hehehe
Regards Martin the Martian,

[Cgswssbmwk100]

It my pads fault!  Every time I type something, it’s goes out and changes my words. Of course if I could spell, it may not be as bad.  Some one told me that it is a product of my times.  He claimed that everyone born in the late fourties are bad spellers today, because we were taught wrong.

[Cgswssbmwk100]

Btw, in my adventure to get this running, I got the radio out after much trying to figure out how th use a piece of hanger to depress those clips and there was a mess of wires on al sort of different connections.  I have a feeling the radio will never work again!  Then a battle with the crash bar.


But the main event was the wiggle and jiggle part.  After an hour and a half of wiggle and jiggle two of the injectors left the rail and the two on the ends pulled out.  I used pliers to pull the two remaining in the engine.  The fuel line on the back of the rail has no slack and there is not enough play to turn the fuel rail so the injectors are facing out.  My hands were cold and stiff, so I didn’t even try to put the injectors back in and re install the clips


So I’m cold and stiff and may try again later, like maybe in May.


Craig

[Martin]

It is easier to assemble the injectors onto the rail with the clips installed. Smear a bit of grease on the "O" rings and push the whole unit back in.
Regards Martin.