BMW K bikes (Bricks)

You are not connected. Please login or register

View previous topic View next topic Go down  Message [Page 1 of 1]


1Back to top Go down    K100 Back from the Dead on Sun Nov 25, 2018 6:38 am

Hman89

avatar
active member
active member
Hi all,

I had been on the search for a motorbike project when i stumbled across a 86 K100 cheap.
The bike had been sitting outside for years and the owner was selling it for parts as it was such a long way from running. A BMW for $300 seemed a steal regardless of condition so home it came with me.
All the body panels (what were left anyway) were pretty much unsalvageable so am planning to do a naked restoration of the bike keeping it all as simple as i can.

    

2Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 6:42 am

Hman89

avatar
active member
active member


    

3Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 6:48 am

Hman89

avatar
active member
active member
While the name 'Kermit' comes to mind that green paint will not be staying!
Intial inspections of the bike showed plenty of grease, oil and dirt along with some butchered electrics. The original contols were missing and a triump set had been crudely attempted to be attached though thinking back on it in not even sure they were attached. The ignition barrel was there but no key only a bored out slot for a flathead , it was a this point i did a quick VIN check to make it wasnt stolen... all good.
The starter motor and a couple of relays were also missing culprits

    

4Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 6:51 am

AL-58

avatar
Life time member
Life time member
At $300 you got a bargain.

Many of us here would have given you $300 for the headlight, headlight shroud and radiator shroud alone. Those parts are made from unobtainium.

It's great to see another one saved,

Al


__________________________________________________
'87 K100RS/HRD sidecar (1100 motor)sc25
'92 K100RS-16v (Paint it Black)

'87 K100RT with Paralever backend

"When I'm too old and too foolish to handle a sidecar I'll buy a Sportsbike"

    

5Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 7:11 am

Hman89

avatar
active member
active member
Thanks Al, i figured if the motor turned out to be no good it was a cheap parts bike so had nothing to lose.
There doesn't seem to be many at all for sale here in Australia so not surprised parts can be hard to find.

    

6Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 7:19 am

Hman89

avatar
active member
active member
Ordered a starter motor and Haynes manual and got to work sorting out the electrics.
Found it was easiest to label all the connectors as i went tracing them out from the wiring diagram and checking for continuity as i went.
For something that was quite daunting it was actually pretty straightforward thankfully.



    

7Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 7:26 am

Hman89

avatar
active member
active member
The flasher unit and temp sensor looked passed their use by date but given the starter relay missing figured i better buy one of them first.
My goal is to get the engine running first so i can assess how far it is worth going with build.
Keeping with the simple things i gave the MAF a clean up


(Have since connected power and checked voltage at the maf as the vane moves and all checks out 👍)

    

8Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 7:34 am

Hman89

avatar
active member
active member
It was now time to tackle the elephant in the room being the engine and fuel system... i apologise as the following pics may offend but well what can i say it was pretty dire...



    

9Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 7:42 am

Hman89

avatar
active member
active member
Was feeling pretty skeptical at this stage but had heard these engines are pretty bullet proof so decided to take the cylinder head off and see what i could do..


    

10Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 10:06 am

Point-Seven-five

avatar
Life time member
Life time member
Welcome! It looks like you have the situation well in hand. There is a great bike hiding under all that dirt and corrosion. A bit of patience and determination will certainly find it.

I'll be watching your progress with interest.


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

11Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 6:31 pm

charlie99

avatar
VIP
VIP
good to see another coming back and in good hands


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
    

12Back to top Go down    Re: K100 Back from the Dead on Sun Nov 25, 2018 11:02 pm

Woodie

avatar
Gold member
Gold member
Truly impressive to see you not be put off by all that needs to be cleaned on your K. It is also great to see that there isn't much that can keep one of these bikes down


__________________________________________________
1985 K100RT
52667
"Keep your stick on the ice. We're all in this together." Red Green
    

13Back to top Go down    Re: K100 Back from the Dead on Mon Nov 26, 2018 5:32 am

Hman89

avatar
active member
active member
Thanks guys, took a few days of soaking and cleaning but the majority of the carbon and grime came off. Its by no means near perfect and im hoping its only mostly cosmetic but i feel as if it would be safe to turn the engine over now.
The actual cyclinders still looked in good shape, can see the original cross hatch on the walls still.
The valve guides felt ok so proceeded to lap the valves to make sure they're sealing as well.



    

14Back to top Go down    Re: K100 Back from the Dead on Mon Nov 26, 2018 5:49 am

Hman89

avatar
active member
active member
Reassembly of the motor from here was pretty straightforward other than me forgetting to put the valve caps on before the cam shafts..... wont be doing that again! Plenty of oil as i went too.
Timing chain didn't appear to be stretched so back on it went along with the tensioner.
Did notice a small crack in the crank case which ill need to address at some stage though. Hoping a cold weld epoxy from the inside will do the trick? Not sure if anyone has any success with this before or other suggestions?


    

15Back to top Go down    Re: K100 Back from the Dead on Mon Nov 26, 2018 5:57 am

Hman89

avatar
active member
active member
Cooling system was next to get some attention. Took all the hoses off and cleaned them up with a bit of warm water. Gave the radiator a flush and cleaned out the thermostat/thermostat housing. No leaks anywhere so im calling it a win for this bit. A couple of the fins got straightened out and it all bolted back onto the bike.

Ive left the oil/coolant pump alone so far as im 99% sure its going to need a rebuild. The bottom radiator sludge had a creamy sludge build up where oil has clearly got into it. The oil in the sump seems to be uncontaminated with coolant so hopefully its only leaked ond way.

    

16Back to top Go down    Re: K100 Back from the Dead on Mon Nov 26, 2018 6:12 am

Hman89

avatar
active member
active member
Finally it was the fuel tank and all its goodies turn. The inside of the tank while dirty doesn't have rust so a good flush is all it needed (several times)



Bit of inox spray and some gentle persuasion and the fuel pump and filter came free. Thankfully the rubber mount and plastic clip is good to reuse, id seen the price of these and was considering which body organ i could do without if it needed replacing.
The filter was stamped 1998 so out with the old and in with the new along with a new fuel pump. Had bench tested thd old one out of the tank by putting power directly on it but it was definitely seized and not coming back.


    

17Back to top Go down    Re: K100 Back from the Dead on Mon Nov 26, 2018 6:50 am

MartinW

avatar
Life time member
Life time member
Pumps can sometimes be resurrected by soaking in white vinegar for a week or two. Once soaked try applying 12v briefly then reverse the polarity. A mate had luck by upping the voltage to 15v briefly and reversing the polarity after soaking.
Regards Martin.


__________________________________________________
K75s Hybrid
    

18Back to top Go down    Re: K100 Back from the Dead on Wed Nov 28, 2018 6:10 am

Hman89

avatar
active member
active member
Ive still got the old pump so will definitely be giving that a go Martin. Would be a handy spare if i can free it up.
Cheers

    

19Back to top Go down    Re: K100 Back from the Dead on Wed Nov 28, 2018 6:16 am

Hman89

avatar
active member
active member
New fuel lines were cut to length and a new (second hand) fuel rail and fuel pressure regulator have been installed. Given the amount of dirt throught the bike i wasnt keen to any chances with contaminating the fuel and blocking the injectors.
The old fuel rail looked like the injectors had been siliconed in so was hoping none had made its way into the injectors.

    

20Back to top Go down    Re: K100 Back from the Dead on Wed Nov 28, 2018 6:34 am

Hman89

avatar
active member
active member
At this stage of the resto the bike is just about ready to turn over for the first time.
Fresh oil, oil filter and coolant was put in. The starter motor installed and not to be left out the alternator was given a quick clean up.




All new fuses were installed seeing as it was missing all of them and a new battery that a mate had spare was hooked up to it.

    

21Back to top Go down    Re: K100 Back from the Dead on Wed Nov 28, 2018 6:50 am

Hman89

avatar
active member
active member
Probably worth mentioning that the bike still didn't have any normal controls/switches installed so i wired up a momentary switch to the start wires as temporary solution.

First attempt to start the bike was rather uneventfull. I could here a relay click when when the ignition was turned on but no action when pressing the start button.
Quick check of the wiring diagram and realised the kill switch is 'normally closed' so twisted the kill switch wires together and the clutch switch wires were still loose so twisted them to gether as well.

Second attempt to start the bike and it was now making noise but not the sound of an engine turning over.... all i could hear was the starter motor turning ovef with no load mixed with an occasional grinding noise...... $#/^&@
All signs pointing to a starter clutch, bit of online research and i was convinced it was the starter sprag clutch.

Started stripping thd back of the bike down so i could get to the auxiliary drive and see whats going on with it.

    

22Back to top Go down    Re: K100 Back from the Dead on Wed Nov 28, 2018 10:33 am

Point-Seven-five

avatar
Life time member
Life time member
Before I tore apart the intermediate section, I would do a search on "sprag" and try some of the methods to free it up.

I am watching with interest and hope you shortly will hear that sweet brick music.


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

23Back to top Go down    Re: K100 Back from the Dead on Wed Nov 28, 2018 10:53 am

92KK 84WW Olaf

avatar
Life time member
Life time member
I have a K like that in my shed, been there a few years.....starting to get itchy fingers now.


__________________________________________________
1992 K100LT 0193214 Bertha Alaska Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 58,645 now 84,600 miles
1983 K100RS 0011175 Fricka 29,000 miles Damn K Pox
    

24Back to top Go down    Re: K100 Back from the Dead on Fri Dec 07, 2018 5:36 am

Hman89

avatar
active member
active member
Been a great project so far Olaf and its only early days!

    

25Back to top Go down    Re: K100 Back from the Dead on Fri Dec 07, 2018 5:44 am

Hman89

avatar
active member
active member
Thanks Point Seven Five, i did have at look some but couldnt get it to work. Was pretty obvious why when i finally got it out!

Rear of the bike stripped i got the old sprag out and found it to be pretty oiled with what looked some damage on the casing.
Doesnt look salvageable but have put it aside for a rainy day just incase. Ordered a second assembly and started the rebuild.



    

26Back to top Go down    Re: K100 Back from the Dead on Fri Dec 07, 2018 5:54 am

Hman89

avatar
active member
active member
Since the gearbox was now separated i took the time to give it a clean up up and install a new clutch as well. (New clutch bolts and retaining nut of course) Rear housing got a scrub too.
There was some nasty looking oil around these parts that is a bit of a concern but have cleaned it for now and will assess again once i can get it started to warm the oil up and give it a proper flush.






    

27Back to top Go down    Re: K100 Back from the Dead on Fri Dec 07, 2018 6:27 am

MartinW

avatar
Life time member
Life time member
Do yourself a favour and fit a grease nipple to the clutch arm. It keeps out the road crud and water.
regards Martin.



__________________________________________________
K75s Hybrid
    

28Back to top Go down    Re: K100 Back from the Dead on Fri Dec 07, 2018 7:17 am

Laitch

avatar
Life time member
Life time member
@Hman89 wrote: My goal is to get the engine running first so i can assess how far it is worth going with build.
This is a course of action all perspective custom builders should adopt before spending on powdercoating and farkle-buying but it doesn't seem to be a popular one. Thanks for the clear photos and descriptions of your work.


__________________________________________________
1995 K75T 68,000 miles
    

View previous topic View next topic Back to top  Message [Page 1 of 1]

Permissions in this forum:
You cannot reply to topics in this forum