Hi Guys,
I'm so happy to have found this forum. I just purchased an '85 K100RS with 186k on the clock. I'm getting back on a bike for commuting(first bike I've owned in 21 years), but having purchased the Beemer, I can see a little light touring coming on.
I really did mean to buy something lighter but saw the ad and was drawn in like it was a black hole. So my Haynes service manual is in the post, and I'm readying myself to address the few "little" problems
that are so far evident.
(weeping a little oil from the sump, timing chain noise low revs, balance front wheel) Well that and a little fairing repairing to be done. Of course the official line at home is that the bike is tip top condition!

Anyway,

The name's Jez.

Hi Ya Jez welcome to the Knuthaus you'll find lots here to read and all the help needed to keep the new mistress in tip top shape. And also an invite (not that you need one as any member is welcome) to our meeting in Narrandera in May. We only made it there for the ride.

Hi Jez and welcome. Where are you based?.
I'll send you a copy of my book that I record all my little purchases since I bought my bike, Frightening reading, don't read before bedtime.
RT

RT wrote:Hi Jez and welcome. Where are you based?.
I'll send you a copy of my book that I record all my little purchases since I bought my bike, Frightening reading, don't read before bedtime.
RT

Ooh RT that is a dangerous thing to keep. Even the Mafia doesn't keep detailed records lest it incriminates them when found.

Thanks guys.

That's a very friendly offer RT, but probably best that I don't see something like that just now. Like a pit pony I'll just keep my head down, plod along with only the next thing in front of me to worry about.

Jez

welcome aboard jez ...

you will learn to love the k ....

happy riding mate

Jez wrote:.... I can see a little light touring coming on.

No, not light touring, take some time off & get out there, see some more of this amazing country we live in and clock up the km's!

Welcome Jez,
Can I ask which bike you bought?
We tend to keep track of the more 'affordable' bikes listed for sale and quietly mock those that try to command high prices and wonder why they don't sell.
I am not suggesting you are cheap or the bike was cheap, but they are on the lower end of the price scale.

Where abouts in NSW may I ask?

rossco

I am cheap, the girls however have developed a taste of things finer than lager, i'm afraid....g

rossco wrote:Welcome Jez,
Can I ask which bike you bought?
We tend to keep track of the more 'affordable' bikes listed for sale and quietly mock those that try to command high prices and wonder why they don't sell.
I am not suggesting you are cheap or the bike was cheap, but they are on the lower end of the price scale.

Where abouts in NSW may I ask?

rossco

Hi rosco,

Yes it's true, I am cheap, and so was the bike. (I've been told that the only difference between myself and a coconut, is the fact that you can get a drink out of a coconut).

Bought the bike on NSW south coast, $1900 with 7months rego as recently advertised on bikesales.

Jez

I too have recently finished bringing an old (04/85) K100rs back from the graveyard, I have (like others) lots of experience and maybe a few parts to share unfortunately, too far to ship from USA.
You will probably find that the seepage from the "sump" is the need to rebuild or replace the water pump/oil pump assy.
The noise that sounds like the timing chain is likely to be a factory defect in the design of the engine output shaft. Probably won't hurt anything for a long time, but it's annoying especially when starting up in the cold weather. There's a BMW Tech service bulletin on how to address that but it requires a lot of dis-assembly. Probably the best time to go at it is the next time you have the trans out for clutch and/or spline service and rear main seal & O-rings.
I truly wish I had gone into mine while the trans was off as it's necessary to remove the bell housing and the lower 1/2 engine case to get it out.
Be sure to get the bulletin before you attempt this as there's some very specific information about keeping the gears properly aligned at the crankshaft to avoid excess whine noise.
Have fun and be careful to not break things in your efforts to diagnose issues. Many people screw up so much stuff trying to find an issue that they have a tough time getting back.
Last tip BMW upgraded the ignition coils after this build. There are 2 types. Yours are specific to the 2V engine.......I got 4V ones on my first try, they are not a fit.
Your coils if they have not been changed probably have black towers where the spark pug wires hook on. The upgrades have orange colored ends on those towers.
IMO the original black ones were "minimal at best" when new. The orange tower ones are SUBSTANTIALLY better. Do your self a favor & find a set of those.
It took me months to find my bad coils and they can give you very weird performance issues.

Yes thanks ibjman,

Looks like some good info to kick off with.

Weird performance issues are what's most consistent about the way it runs at the mo'.
But lordy when it hits that sewing machine band, it's like there was nothing wrong with it, for that time between lights, me and the brick are young again. (well OK I'm not that old, I'm only beginning my creaky phase.)

Pheonix ..... ha! from the ashes, how apt.

Where are you living Jez?

Anywhere near Sydney?

Mr Klompy would love to come help sort your problems.

When he is done he will have a look at why your bike is not running right.

Tis true Rossco is very generous with my time .....oh I know where this comes from once there was a K owner we will call him ....."barry" thought that his alternator was about to explode with "ticking" noises etc and it turned out to be a cracked coil arcing out ( best seen in partial darkness ) once fixed no noises and a bike running very smoothly...those monkey nuts in the alternator was another story ..if you are a local don't be a stranger Jezza...we can all meet in a pub carpark where all the best K work is done, although certain parts of Castle Hill are starting to get used to K bikes zooming up the streets.

There is an S shaped rubber hose about the diameter of your thumb that runs between the top of the crankcase (vent) up to the side of the intake plenum located just above the aft end of the fuel supply rail. It will oft be found cracked and sucking air. It is necessary to remove the air filter box to get at (replace) it (a challenge all by itself) but you might just as well get used to removing the filter box, cause you'll probably do it several times.
Basically,
#1 Remove the intake snorkel
#2 Unclip the 3 lid retaining clips
#3 Slightly lift the box lid & slide the cartridge out (mark it, only fits in one way)
#4 loosen the Large round hose clamp securing the Big plastic Air elbow between the lid and the injector intake plenum box (The clamp at the injector end, NOT the clamp at the box lid end)
#5 Work the end of the big air intake elbow loose from the injector plenum (stuck)
#6 Slide the airbox cover out the right side of the frame and hang it on a coat hanger there with it's (Air flow meter) wiring still connected
#7 Remove the 2 bolts securing the airbox bottom to the top of the engine and remove the bottom. (special attn. to 2 washers on top of the engine but under the box)
EASY
PS while you are in there you may want to replace the multi (elbowed) rubber fuel hose between the fuel pressure regulator outlet and the fuel tank return port. (like $50 from BMW) and the hose between the rear end of the fuel rail and the fuel pressure regulator. (Any high pressure Fuel injector specified fuel hose can be used to replace that hose as it's not pre-formed).
Last. Do not put all the fairings back on the bike till you've had some test miles cause you'll get very fatigued at putting these on & taking them off multiple times....lol

[quote="ibjman"]There is an S shaped rubber hose about the diameter of your thumb that runs between the top of the crankcase (vent) up to the side of the intake plenum located just above the aft end of the fuel supply rail. It will oft be found cracked and sucking air. It is necessary to remove the air filter box to get at (replace) it (a challenge all by itself) but you might just as well get used to removing the filter box, cause you'll probably do it several times.


You are kidding right? Does the airbox really have to come out to replace the breather? I just put the bloody thing back in! I didn't have the breather hose with me but I read in the portal that it was a 5 min job to replace, so I thought it could be done with the airbox in place.

I did one on the K75 a few years ago by taking the coils and TPS off to make a bit of room, it wasn't a easy job but better than pulling the fairing etc off. The problem can be if the clamp on the engine case is in an easy position to get at the screw on it.

Rick G wrote:I did one on the K75 a few years ago by taking the coils and TPS off to make a bit of room, it wasn't a easy job but better than pulling the fairing etc off. The problem can be if the clamp on the engine case is in an easy position to get at the screw on it.

While I had the airbox off, I positioned all the clamps I could see or reach so that I could undo them with a screwdriver or socket wrench. Will let you know how I go when I get the breather tube.

I stand humbly corrected........Oh Jedi master.......lol

Yes Alheng,
I replaced my breather without removing anything, it was straightforward on my RS, perhaps I was lucky?

Paul.

ibjman wrote:I stand humbly corrected........Oh Jedi master.......lol

Hi Jez,
Great to have you with us, read the "you have just bought a K100 so what now?" a good read and lot's of good stuff there.
Regards,
K-BIKE

Hi all,

Thanks for all the good oil so far. I replaced the crank case breather hose today. Thanks to the mechanic of the PO who kindly left both hose clamp nuts facing the right way! It made it very easy.
I'm about to start another post, with pictures and video, just to show you what I have, and what I need to deal with.

Kind regards and safe cycling,

Jez.

I'll post it in Tecnical Repair & Troubleshooting.

I'll title it, "Noisey Idling 84 K100".

Gidday,

Welcome to the site and like a fish out of water and also a kid with a new toy, I to are stumbling my way around a "new to me" K model beemer which is sitting out in my resto shed.

Pulling apart, check, clean and re assemble has been a common theme for me and I am learning heaps has I go about it, together with the hours of reading and trolling through technical info from this site, I to have a used manual in transit somewhere which I'm guessing its probably between Hawaii and Canada as we speak and it should be landing on my doorstep soon which will no doubt surely enhance the tactile relationship between man and machine over the next few months...


BTW - I looked at that RS on Bikesales for a few day, just a little to far me to go to inspect as my work was not allowing me to escape with ute and cash in hand..

It will clean up very nicely, best of luck and enjoy the many hours of man/bike/shed bonding time together with your favourite "Barry White" greatest hit cd rumbling away in the background as you slowly make your way through a 750ml bottle of smooth aged bourbon, nip by nip, sip by sip, by the amber glow of your rustic home made woodfire which still stands proudly in the corner surrounded by half cut corrugated iron sheets with "BHP Steel Co." stamped into them and was skill fully and painstakingly welded together and constructed from a few truck brake drums that you so dragged home from the local "Rotary Club" swap meet which is generally held on the first Saturday of November every year, rain permitting of course...

Sheeze Grant, that was freakin' poetic man.