Ha,
I probably would've asked the same question!

I gotta get the right size shims obviously, but how to calculate the shim sizes needed is at the moment a mystery, given that I have no measurement of how tight they are as the clearance (if there is any) is so small tat I can't presently measure.
I see that The Bins have a kit, but for all I know I'll use up all the 1 size.

Just get 0ne small shim like a 220 and swap it to each tight one.  The BMW TC NSW does have a shim kit for members if that helps. That alone is probably worth the membership.

OK
got hold of a valve lifter and a 2.05mm shim and did the rounds of the head with it. (got a lot better at the removal and refitting by the end too)

The result weren't great;

With 2.05 mm in place

1   In   0.45mm   Ex   0.33mm
2   In   0.43mm   Ex   0.1mm  (best possible clearance-0.15mm with 2mm shim in place)
3   In   0.38mm   Ex   0.25mm (best possible clearance-0.3mm with 2mm shim in place)
4   In   0.4  mm   Ex   0.2 mm  ( best possible clearance- 0.25mm with 2mm shim in place)

So it looks as though the clearances can't be dragged back in by smaller shims as I believe they(the shims) only go down to 2mm and the required Exhaust clearance is 0.25mm.

I'm searching at present, the causes, but everything seems to point to a head job. (phht!)

Jez

:pale:

Looks like it does need attention, It may have been done by somebody who didn't consider that the clearances need to be set before the head goes back on then did the best they could.
Setting the initial clearances can take a while but if you go ahead its best to do it with the springs out and the cam bearing caps off and do one valve at a time and you do need some way of doing the stems square when you grind the ends. Set each valve to 2.50mm -2.65mm shim size. Also you may need to shim the springs so as to get good seat tension.
I would try to get a good second hand head.

Jez wrote:I'm searching at present, the causes, but everything seems to point to a head job.

I would guess this is caused by using unleaded petrol for most of its life.
This early model should run with lead substitute added.

Yes indeed Inge, When I bought the beast, I asked the PO what it had been running on...... Unleaded.
I should have searched this subject myself, still I think the way it's been running, the damage was done long ago, I'll know more when I remove the head.

Now.

Off with her head!
:king:

The head gasket was still in tact.

I don't think the valves are burned, but need grinding, something that's beyond my workshop.


The timing chain looks a little slack when laid out and set in a curve, the chain vaults 60mm in the apex of the that curve above the ends.

The guides look fairly new but I'm not too sure about that chain, any feed back would be appreciated.

So now it's the search for either a replacement for the head as Rick suggests, and/or a cap in hand visit to the local head shop to see what they reckon having no idea about the cost of doing the job.

Jez.

Inge K. wrote:

Jez wrote:I'm searching at present, the causes, but everything seems to point to a head job.

I would guess this is caused by using unleaded petrol for most of its life.
This early model should run with lead substitute added.

Does anybody actually do this tho? Does it say anywhere in BMWs literature that this is the case? What did they have to change to enable safe use of unleaded? (valves and seats of different alloys?) 

Seems to be a debatable issue. Im very interested though as my engine/head is an 84. She runs beautifully though. Well, id love one of you blokes to take it for a spin and tell me what you think, as its the only K ive ridden and have nothing to compare it with. Smooth though and is torquey nearly everywhere. 

Keen to hear how you proceed Jez, particularity with how much a head shop (that phrase reminds me of Amsterdam) quote you. 

Personally, I would put a new timing chain in. But thats just based on the fact that its old, likely worn, not overly expensive to replace, and your balls deep into it now so why not?

I've taken the plunge, Impatient as I am, The guy has quoted me $280 BUT I need to supply 4 exhaust valves and the stem seals. Meh, not toooo bad depending on what I might source the exhaust valves at . They cost and arm and half a leg each new. At least I know when the head returns it'll be in much  better condition than I could've got it into.

So, any body got 4 exhaust valves in serviceable nick?

My brick is sitting on bricks.

Jez.

Oh yeah, not to open the worm can, but Ol' Mate at the head shop reckons, it'd run on anything but E10. (10% ethanol), just sayin'.

Most people don't use the lead substitute because it takes a long time to damage the head and many see that as no damage done. The lead worked as a lubricant for the guides and also helped to transfer heat from the valve head to the seat and head to keep the temperature of the valves down and stop erosion of the metal and distortion of the valve head.
The heads that fare worst are the cast iron heads with no seat inserts.
The head would be salvageable but at what cost,if you bought it along to me to do and assuming I had all the good equipment I would tell you that you won't get out for under $400 and quite possibly more like $600. Setting the clearances after reclaiming the seats and valves is a time consuming process and on top of that checking spring seat tension and correcting that can easily take a full day.
You would probably have to buy a complete engine to get a head as they don,t often come up for sale separately. My advice is get a late model engine (1990 or later) and replace the lot unless you can get just a head.
A gasket set alone is $200 from motobins

might have some valves here jez

ill have a look on the weekend if you like  not sure of vintage though ...probably 85-86  or so

have seen some good alternatives to valve seats on the net ....pricy, but you get the idea
 

have a look here


http://www.mez.co.uk/mezporting/page4.html#Lead Free Seats

cheers

Thanks Charlie.

Got some coming from Italy. Got a set of new ones for $160ish delivered. Not too bad considering the local supplier wants $250 each! Still everyone's advice is that it would be $400-$500 for a reco head, I won't be far off that. I'm an impatient sorta bloke, (self confessed), so it's not a huge shock, but I think it's as good as I can get. I just hope that everything down stream handles the new stresses.

I'm just keen to know what to expect when I open the throttle at any given situation.

Jez

PS
Thanks to all who have advised so far, Once the bee is in my bonnet, I'm all over twenty different sources looking for a solution, often with a more expensive solution. When I'm closer to retirement with another bike to ride while the other one's being fixed, perhaps I can slow down with my problem solving.

Regards,

Jezza.

Got the shiny (old) new head back from the shop, see?



Got all my bits n bobs in the mail, got it all back together, hit the button and Vroom! F*&#'n Beeooooty!
Runs 200% better now. Idles, accelerates smoothly,doesn't quit, just like a real engine

Still a couple of probs, though all seems trivial after having the head off and changing chains etc, I've taken taken the cover off again this arvo as the valve clearances weren't quite right. Not as bad as I expected, only two shims to change, I was hoping for worse as the reason for taking it off was valve noise, tick tick tick tick, (at least that's what I think it is).
I certainly didn't like the look of this, the corresponding exhaust and inlet valves don't line up, should the intake valve 3 pictured below lead the exhaust 4 (pictured at bottom)by that much?............

Intake 3 lobe


Exhaust lobe 4



At any given part of the phase, the intake valves are opening about 45 degrees before the exhaust. Is this right? That is to say when the cam for exhaust port 4 is pointing at 180 deg from it's shim,lets call it 3 o'clck the intake one for 3 is at 1:30 if viewed from the front of the bike.

Thanks again for all help thus far, I truly have been Miyagied. ( That's when instructions are passed on without formal training or direct advice, like waxing a car, wax on wax off, instead of karate lessons..... you like Mr Miyagi)

Jez

This is how the valve timing is supposed to be but it's a bit difficult to visualize when I haven't got an engine in front of me
Valve timing — at 5/100 preload and 3 mm (0.12 in) lift UK models
Intake opens…………………………………………………………………… 5°  BTDC
Intake closes…………………………………………………………………… 27°ABDC
Exhaust opens…………………………………………………………………. 28°BBDC
Exhaust closes…………………………………………………………………  5° BTDC
The US models open 10° later on the inlet.
Where is the inlet lobe relative to the exhaust lobe on TDC off compression, they should be with the inlet just about to open and exhaust closed or very close to closed on each cylinder
If you want to check using a degree wheel give me a yell as I have a good one you can print out and stick to some cardboard or plastic.

Just a note, Photos added and post edited for last post. Might take you up on that degree wheel Rick PM sent.

From the Haynes manual:

Thanks Inge,

This is exactly the method I followed, mating the sprockets to the chain if not engaging right on the marks, by rotating back towards the drive and picking up the next available link.

One thing I didn't do was count the links on the new chain, I read here somewhere that Rick I think, had a chain that was a link or two too long from having a different model's chain? I assumed the chain to be the correct one as ordered from Motobins.

While I have the valve cover off, I s'pose there's no harm in checking the marks again. Jeeze I'm getting sick of dismantling/reassembling but I am getting quicker at it.


cheers,

Jez

That was TWB and he got a K1100 chain which is 2 pins (1 link) longer. Apparently it was OK but had no adjustment left when the slack was taken up.

it was rick fortunately help was close by .

jez the timing of the can wheels is dependant on the top run of the chain ...so no slack there ...the slop point is the return or lower run of the chain back past the cam chain tensioner on that bow styled chain runner ...in fact you should be able to set it up without the tensioner being installed .....then after its right, slide the tensioner up  (cable ties to hold it down in the compressed position as it is located) ...then after bolting it up cut the ties off ,

hope that helps some

RicK G wrote:That was TWB and he got a K1100 chain which is 2 pins (1 link) longer. Apparently it was OK but had no adjustment left when the slack was taken up.

Did run into that thread yesterday, and thought so too.

But 100 & 1100 did have the same part #......could be from a 1200,
which have a different #?.

He gave me that chain and it is still in the cupboard so I will go and measure it, but not now it's dark and the mosquitoes
are out hunting for humans.

Just wanted to pinpoint that 100 & 1100's have the same chain....to avoid to much headscratching for future readers.

If you measure the chain..........we still don't know which model it was meant for, and that isn't important at all...it just clogs up the useless info departement.

agree inge ...in any case it was 2 links longer

but just enough to be at full chain tensioner travel  as a new item

Hi Guys,
Well I have been working on the bike since I last posted, but my internet has been running so slow that I haven't bothered updating let alone trying to upload images. I did discover though that one of the cam sprocket's locating pin was partially sheared.  Enough perhaps to kick the sprocket out by a half or three quarter link.
Well in a fit of inspiration, I found the hole at the rear of the pin (seemed to be spot welded or such) could be drilled out, (see Inges Haynes manual photo above) I brought a 6mm long 4mm coutersink high tensile bolt, countersunk the hole, threaded it and got ready to re-assemble. The washer would be insurance against the bolt unscrewing as it sat flush on top of the countersunk head.

Upon re-assembly, I realised in the haste to prove my mechanical brilliance, had somewhat negated that mechanical brilliance! The wise words of my son burning in my ears, "Measure twice, cut once." Nothing like  your own advice cutting like a scalpel.
I had countersunk the wrong side of the sprocket.

After much colourful language and some words even I don't know. I made another hole diametrically opposite and threaded and countersunk it. The only concern being the fact that there is a "roll off" on one side of the sprocket. ie one side is very square to the back surface of said sprocket and the edge to the front side it a little rounded.(see Inges Haynes manual photo above) It's on back to front now. I have since sourced a "new" set and will put them in over the chrissy break. Just to rub salt in, the marks have not lined up any better.

I made a half arsed attempt at a TB balance as the valve clearances are as good as they've been in my ownership of the bike, but the gauges are not it seems in the range of what's required (I think they are a fairly cheap set  borrowed from a mate)

A couple of weeks ago I went to a K bike fiddlers "shed sell out" and I rode there, but the donk has gone back to the little occasional knock, it was the fiddler that pointed out it was missing. I hadn't never
 either recognised nor thought of it as a miss. We tried another ECU, no different, I have brought a "new CPU off him, to check that, I received some "new" recco Bosch injectors from the US, So I'll pull it down aGAIn (!) and check the CPU in the process, put the "new" sprockets in and fit up the new injectors. (I'll get yours back to you Klompy).

I have a little bit of work to complete before taking a Christmas break ( don't tell my doctor) and then will slowly, slowly get the bike bits back together. I have no choice at the moment due to a heart attack (last weekend) that has put the brakes on in everything that I do at present. Bit of a shit, but at least I'm still here to bother the BMW K100 oracles for a while yet.

Jez

what the ?!!! 

crikey jez take it easy for a while mate ...that some serious stressing out there

get well soon ol mate .....with the belief that you will get there ..but no particular rush is needed

cheers !

Heart attack quite separate from the bike palava Charlie. I still don't know why, but I'm neither a stressful chap, unhealthy bloke or an aged cheeseburger slurpin' couchpotato. (Enjoyed the occasional durry though, that'll have to stop). It happened during a leisurely surf down the coast while paddling easily around in small surf. I can blame my genetics I think.

Jez.

I have to agree with Charlie Jez.

I am guessing in the surf is not the best place to have the ticker go haywire.

Take it easy. I was going to offer any help you may need (K wise, I am a hopeless thoracic surgeon), but by the sounds of it you are well on top of stripping (again) and rebuilding.

If you do need a hand, just holler.

rosskkko

Hang in there Jez and look after yourself. I had two of those events over a 6 month period before the big decision to put the zipper in the chest. That was 8 years ago at age 55 and I'm still riding. It was the genetics that got me was well - I had no other common risk factors.

Charlie , you had better get off those smokes. You just have to find another excuse for stopping on a ride.

Cheers

Well after much toing and froing with my interweb provider it seems that they've fixed the crappy connection to my house from the street and speeds are back up.
I know how you all like pictures, and now it doesn't take 3 hrs to upload one, I'll give thee a quick pictorial update of the stuff I've been trying to illustrate with words till now.

Here's the partially sheared pin in the cam sprocket, dunno if this was enough to send it out of whack but I've new ones to install.



Grrrrr measure twice cut once.


I'm in the throes of changing to higher handlebars at the the moment so have been fitting all the little bits Ive been collecting over the past month or two;
Recon squirters (injectors)
old new CPU
new set of gears on the odo,
If you haven't seen my post by the way in WTB, I need a RT non ABS top brake hose.
Once that's back together (probably later today) I'll take those MF'n covers off one more time and swap out the old cam sprockets and (fingers crossed) Bob will be me mother's brother!

Thanks for the well wishes, apart from going slightly stir crazy, I'm feeling fine, they've fitted me with a chemical govenor, so I can't get my revs above about 1800, ha relax everyone says, got no choice in that one.

Jez

(thought I had more piccies, must be on the work pooter)