Hi Guys,

Bought a K100rs 1985 model bit rough on the outside and very rough idle, anyway spruced her up a bit, new plugs, battery and cleaned up the Injection processor connection plug and she rides really nicely now so I decided to renovate this one back to original state.

Just completed an oil and filter change and while waiting for the oil to come to the sight glass I missed it and over filled her. Started her up to get oil into the new filter to see if I would then be at MAX on the sight glass, unfortunately still over. Emptied about 1 litre out to MAX on the sight glass, all seemed well with the bike.

Done a couple of shortish rides and now each time I start her there is quite a lot of smoke and she is now running a little rough, not as bad as when I bought her but rough all the same.

I treated the bike to PENRITE fully synthetic 15W- 50, do these bikes not agree with fully synthetic ? or is the overfilling stuffed up the bike ? is the running rough just a coincidence ? 

Any advice would be greatly appreciated.

Andrew

If you're parking the bike on the sidestand while the engine is still hot then, yes, next time you start it will smoke to a greater or lesser degree as the thin oil will have crept passed the piston rings and into the combustion chamber. Overfilling won't have helped but - they all do it.

As for semi-synthetic; some on here have had trouble with it leaking past seals and other haven't. I have used semi-synthetic without problems but I tend to stick to dinosaur pee normally.

Running rough could be a number of things. I'd favour air leaks around the inlet intakes (the bits that connect the plenum chamber to the injector bodies) and the inlet spigots (the bits that connect the injector bodies to the cylinder head). It's most unlikely that they will have survived this length of time without cracking. Also check that the blanking plugs are still on their spigots on the side of the injector bodies (cylinders 1 -> 3 only - no.4 has a vacuum takeoff). Most likely they're either cracked or missing.

New parts for all of the above are available from Motorworks and Motobins in the UK; Motorworks also do good s/h stuff.

Dai wrote:If you're parking the bike on the sidestand while the engine is still hot then, yes, next time you start it will smoke to a greater or lesser degree as the thin oil will have crept passed the piston rings and into the combustion chamber. Overfilling won't have helped but - they all do it.

As for semi-synthetic; some on here have had trouble with it leaking past seals and other haven't. I have used semi-synthetic without problems but I tend to stick to dinosaur pee normally.

Running rough could be a number of things. I'd favour air leaks around the inlet intakes (the bits that connect the plenum chamber to the injector bodies) and the inlet spigots (the bits that connect the injector bodies to the cylinder head). It's most unlikely that they will have survived this length of time without cracking. Also check that the blanking plugs are still on their spigots on the side of the injector bodies (cylinders 1 -> 3 only - no.4 has a vacuum takeoff). Most likely they're either cracked or missing.

New parts for all of the above are available from Motorworks and Motobins in the UK; Motorworks also do good s/h stuff.

Hi Dai,

I don't put her on the side stand at all due to that very problem, I am using FULLY synthetic and has been the only change so reckon could be the oil creeping past seals as you suggest.

I'm going to give the synthetic another day to get its act together or I go back to " dinasaur pee " 

Will take a look for air leaks, did try the technique of spraying cold start across the area to see if a rise in RPM and nothing. Will check out the connections more thoroughly as you suggest. 

Did buy her cheap from a garage with a view of converting her but she rides so nice I couldn't bring myself to put her under the knife ( disc cutter )  . I hope to bring her back to her original state.

Thank you

Glad to hear that a new owner isn't doing another cafe job.  Seems that's all that people buy bricks for these days.

I run full synthetic Shell T6 Rotella 15w40 in all my bikes and have no problems with excessive smoking or rough running. 

Has you bike sat unused for any length of time?  If so, you could be dealing with stuck rings.  I have one bike that is finally loosening up after about 6000 miles and now smokes a lot less and at the same time uses less oil as well. 

If indeed you are burning a lot of oil, you may be oil fouling the plugs which can make ignition a bit hit or miss. 

Before I did anything else I would lower the level from the max point to the dot in the center of the sight glass.  That may help with the smoking.  Then I would check my plugs after a good hard run to see if they have a lot of carbon build up on the electrodes.

I've been using Mobil 1 15-50 full synth in my bikes for years and still do. It does not cause any more smoke than any other oil.

After you turn the bike off and tilt it to the right for 10-15 seconds.  This will let the hot oil behind the pistons drain back into the sump a little better, leaving less behind the pistons to seep past the rings.

How would the bike know where the oil comes from to make it run rough?
I would suggest that if, as you say you overfilled it by a whole litre, then you need to get yourself a manual telling you how much oil it should hold in the first place.

Before I did anything else I would lower the level from the max point to the dot in the center of the sight glass.  

I find if I fill to the top of the sight glass it consumes that oil until the red dot is reached then it remains stable. Its also easier to see how much oil you have.

Thank you for the advice dai, duck , point-seven-five and k100virgin makes good sense

Thank you too Bob t your a genius

Andrew

The K100 was designed to run full synthetic. If the bike is used to fossil oils there can be some crud build up around seals etc. Full synthetic being more detergent than fossil oils, will clean this out, then you can get a little bit of weeping.
Also, full synthetic molecules are much smaller than fossil oils, good for engine lubrication, but it can get past worn seals where fossil oils wouldn't.
Always a good idea to pre-fill the filter otherwise start-up and initial running will be with no oil.
I'd have to agree with BobT. Measuring the correct quantity is the best way to go about filling with oil.
Check your SPs and exhaust for oily/sooty residue. You may still have some residual oil in the cylinders from the overfill.

K bikes were not designed to run on full synthetic. If they were then it would be specified in the owners manual.

In fact, they are designed to run on regular motor oil.  It's advisable to break a K engine in (not really an issue these days) on conventional oil until the rings have broken in.

After that it doesn't matter much if you run synthetic or dino oil.

duck wrote:K bikes were not designed to run on full synthetic. If they were then it would be specified in the owners manual.

In fact, they are designed to run on regular motor oil.  It's advisable to break a K engine in (not really an issue these days) on conventional oil until the rings have broken in.

After that it doesn't matter much if you run synthetic or dino oil.

+10

No one ever designed a bike just to run on any oil. The bike was designed to transport the rider over distances, the oil specified was the best available at that time.

I run all my K's on fully synthetic without any issues.

I wonder if the motor has pumped some oil up the breather into the airbox?
Whatever you do, get the excess oil out of the motor asap. 

Hi Guys,

Thank you for the advice,

I did take out the excess oil once I realized my mistake, won't be using the eye glass method in future 

Stayed with the Fully synthetic as after a couple of rides the smoke reduced and now stopped and she runs sweetly again. Not quite sure why the rough running but not complaining now she'e sorted herself out 

Back to renovating her, love this bike

Andrew P

Also don't believe the quantity that BMW tell you it is too much. I usually fill the filter then put 3 Lt in and run it then top it up with probably 300ml. If you put the recommended in then it will go over. Never ceases to amaze me how manufacturers can put so much thought into a vehicle and then get basic things wrong.

I'll never get the pre-filling the oil filter thing. Sounds messy to me. The easiest way to fill the filter is to install it, put some oil in the bike and run the engine.

I usually install the empty filter, put enough oil in the bike so its in the upper half of the sight glass and then run the engine for a couple of minutes. Then I let it sit for a few minutes to let oil drain back into the sump and then top it off to about 2/3 in the sight glass. Then check it again after the next ride just to be sure.

The pre filling of the filter is to save the wear on all of your bearings when you start the engine after an oil change. The first 250 ml is better in the bearings, with a pre filled filter, rather than filling the filter with dry bearings.

BobT wrote:The pre filling of the filter is to save the wear on all of your bearings when you start the engine after an oil change. The first 250 ml is better in the bearings, with a pre filled filter, rather than filling the filter with dry bearings.

I'll second that Bob. 

duck wrote:K bikes were not designed to run on full synthetic. If they were then it would be specified in the owners manual.

Yeah, OK.... might've been an over statement on my part but IMO you're better using a full synthetic in a K-bike. Didn't BMW market a full synthetic oil for use with the K series??

Andrew P wrote:....
Stayed with the Fully synthetic as after a couple of rides the smoke reduced and now stopped and she runs sweetly again. Not quite sure why the rough running but not complaining now she'e sorted herself out
....

Running rough due to excessive oil in the cylinders would be my guess.
Glad to hear she's running sweet again.

BobT wrote:The pre filling of the filter is to save the wear on all of your bearings when you start the engine after an oil change. The first 250 ml is better in the bearings, with a pre filled filter, rather than filling the filter with dry bearings.

The oil filters I buy don't have any bearings in them.

We always filled the filter with oil before installing it, otherwise the first strokes for the oil pump are spent filling the filter before the bearings get any oil.

In my experience too the oil quantity in the manual is significantly overstated.

duck wrote:

BobT wrote:The pre filling of the filter is to save the wear on all of your bearings when you start the engine after an oil change. The first 250 ml is better in the bearings, with a pre filled filter, rather than filling the filter with dry bearings.

The oil filters I buy don't have any bearings in them.

  and more to the point why would you want to fill a filter with dry bearings

92KK 84WW Olaf wrote:We always filled the filter with oil before installing it, otherwise the first strokes for the oil pump are spent filling the filter before the bearings get any oil.

In my experience too the oil quantity in the manual is significantly overstated.

Every time you turn the bike off "all" the oil drains back into the sump. So every time you start the engine the bearings are without oil for the first few strokes until full oil circulation is achieved. Which of course they are not since there's a film of oil left on all of the engine internals.(Unless you let it sit for a few years.)

I am with Duck on prefilling the filter.  As long as the engine is restarted within a short time of the oil change there will be enough oil left in the bearings to protect them for the few seconds it takes to fill the oil filter.

RicK G wrote:

duck wrote:

BobT wrote:The pre filling of the filter is to save the wear on all of your bearings when you start the engine after an oil change. The first 250 ml is better in the bearings, with a pre filled filter, rather than filling the filter with dry bearings.

The oil filters I buy don't have any bearings in them.

  and more to the point why would you want to fill a filter with dry bearings

Wow what a can of bearings...sorry worms I've opened 

duck wrote:

92KK 84WW Olaf wrote:We always filled the filter with oil before installing it, otherwise the first strokes for the oil pump are spent filling the filter before the bearings get any oil.

In my experience too the oil quantity in the manual is significantly overstated.

Every time you turn the bike off "all" the oil drains back into the sump. So every time you start the engine the bearings are without oil for the first few strokes until full oil circulation is achieved. Which of course they are not since there's a film of oil left on all of the engine internals.(Unless you let it sit for a few years.)

But surely after the engine has been shut down the complete lube system is still full, primed and ready to pressurise immediately. I obviously get what you're saying in that the bearings still have  some oil present but it's meant to be forced lubrication.
I fill my filters because I like to give my K's every chance I can-they're precious aren't they?

Mike

You are right, the entire system is still full of oil, including the filter. So even though the oil drains back to the sump the moment the starter turns you have oil pressure.

But after an oil change with an empty filter it has to pump about 250ml into the oil filter before the bearings get oil pressure. The oil pump spec gives you the flow rate for the pump.

Given that some of us are dealing with engines over 30 years old that does make a difference. Same too with achieving high mileage on engines.

Any time we ever rebuilt an engine we always turned it over by hand after everything was done with oil in to make sure oil was in every little place and being fed into the bearings before putting in the plugs and firing up. With power on you do this until the oil light would go off.

Has anyone here EVER heard of a K bike engine failing due to internal engine wear caused by lack of lubrication?  I never have.

The most common causes of K bike death are a crash, electrical issues or the rest of the bike just plain wears out.

Duck is right on that one. My friend who has worked on Ks since they came out told me the only reason he ever had to take a head off a K was accident or external damage and not from mechanical failure.

In the normal scheme of things the oil or no oil in filter isn't going to make a huge difference. 100,000 miles is what 20 oil changes.

But if you are going on to mega miles the details are what make the difference.

I have friends who run engines into the hundreds of thousands of miles and say that this is the difference in prolonging the life of plain bearings which are found at the main bearings, big ends and camshafts. Regular oil changes,  prime the filter and an engine will virtually last forever if all the other stuff is kept in good order.

92KK 84WW Olaf wrote:......
I have friends who run engines into the hundreds of thousands of miles and say that this is the difference in prolonging the life of plain bearings which are found at the main bearings, big ends and camshafts. Regular oil changes,  prime the filter and an engine will virtually last forever if all the other stuff is kept in good order.

I would agree with this but there is a lot of debate as to whether to or not. My thinking is that its gotta help minimise wear in the long term. Only takes half a minute, so why not. I've always done it and will continue to do it.

I've certainly heard of valve guides wearing. Whether or not that could've been prevented or postponed by pre-filling the oil filter you'd never know. I'm not too sure but maybe even the water/oil pump gets stressed for those few seconds without oil.

K engines are very forgiving and very resilient and they give us a great ride. Why not give a little love back with some attention. Probably do you more good than the bike actually. Its a bit like foreplay. I certainly enjoy riding my Sweet Thing more knowing I've done my best to maintain her parts with some good lubrication. Just my thoughts

Changed the oil and filter this morning, filling filter before replacing. Started on 'choke' and it took 4 seconds before oil light went out with a drop in revs as pressure built up. Bike had stood 12 hours since last use.

JGT wrote: Started on 'choke' and it took 4 seconds before oil light went out with a drop in revs as pressure built up. Bike had stood 12 hours since last use.

If I were changing oil in engines not run for 12 hours, I would definitely charge the filter with oil before installing it, too, but when I change oil in any engine, the engine has been run until it has warmed up. More oil flows from it faster that way. Filling an oil filter before installing it seems like a toast to the bike's faithful service. As a ritual it's appealing.

I don't love my bike; I don't have that much love to spread around. I do try to respect and accommodate its needs. That seems to be enough for both of us.

Well, the obvious thing to do is a complete PITA on a brick. On the Guzzis I just pull the spark plugs and crank until the oil light goes out. You can't prime the filter on a Guzzi because the bugger's mounted the other way up compared to a brick. The Blandit can just go suffer...

Even when I've filled the filter on an oil change I never use fast idle on the first stab at the button. 
I just let it spin away until the oil pressure warning light goes out. Only then will I use the fast idle lever....but that's just me. 
We all dance to a different tune don't we?

Some of the argument probably borders on being pedantic but that's not necessarily bad.

Am I right in thinking the only bearings which are lubricated under pressure are the main bearings, big end bearings and camshaft bearings? Splash lubrication looks after everything else?

i always fill the filter before installing it , just because i can , but on my toyota avensis it is not an option unless i flip the car over on the roof 😋

i believe that on many engines the oilfilter is located in such a way that prefilling is not an option , and yet most engines last as long , or longer than the rest of the car 👍

k-rider

92KK 84WW Olaf wrote:Am I right in thinking the only bearings which are lubricated under pressure are the main bearings, big end bearings and camshaft bearings? Splash lubrication looks after everything else?

Pretty much the same on most engines.

He he best not mention a Kawasaki Z1 then. But as you say it's pretty much that on most engines.