Whats the best engine oil to use in these? Synthetic or mineral?

The best engine oil is just that, you can use it in any engine. 
Some will tell you that the engine was made for a mineral, but I have yet to see an engine made for just the oil. Most engines consist of bits of metal rubbing together so, new or old, they will enjoy a good oil. The riders handbook will tell you what was specified when the bike was made, but I am a believer in using the most modern oil that I can. If you think about it the handbook also tells you what tyres to use but people tend to use more modern stickier tyres.
I use a 5W40 full synthetic in mine. My reasons are: The 5 part makes sure that the oil is thin enough to lubricate the whole of the engine within seconds of a start. After a short run it will be the 40 number but will be thinner than it was when cold. I use synthetic because it withstands heat much better and will not degrade till it reaches around 160c (mineral starts degrading around 130c). The last reason is that synthetic is very cheap over here and I tend to leave it in for anything up to 10,000 miles.
Many people will be along soon to tell you that they use something different and oil threads tend to get very long.

15w50 Napa brand full synthetic (Made by valvoline). Unless you are breaking in a new motor there is no good reason to use mineral over synthetic. Race cars run synthetic.

How much oil does your K bike use?

Mine burns a quart in about 1200 or so miles, so synthetic doesn't make much sense since it isn't in the engine for 5000 to 10,000 miles.

sugarhillctd wrote:How much oil does your K bike use?

Mine burns a quart in about 1200 or so miles, so synthetic doesn't make much sense since it isn't in the engine for 5000 to 10,000 miles.

It still makes sense because it lubricates better and is not damaged should it get too hot.
What you have said is like saying I buy cheap rubbish tyres because I keep wearing them out!
By the way your bike in your avatar looks fantastic. I would love a white 16 valve rather than my bland looking black one.

Good oil and frequent oil changes make all the difference to longevity and wear. Most wear happens on start up and cold so the thinner oil makes sense-it gets there quicker. If you do your own changes go for lower mileage changes. Its short journeys wear oil out quicker than long ones.

bikerboy wrote:

sugarhillctd wrote:How much oil does your K bike use?

Mine burns a quart in about 1200 or so miles, so synthetic doesn't make much sense since it isn't in the engine for 5000 to 10,000 miles.

It still makes sense because it lubricates better and is not damaged should it get too hot.
What you have said is like saying I buy cheap rubbish tyres because I keep wearing them out!
By the way your bike in your avatar looks fantastic. I would love a white 16 valve rather than my bland looking black one.

True, but the last few years have been low distance (not over 5,000km- business has been too busy) and I change it every winter.
I did try synthetic in my previous '93 K1100RS but it seemed to burn faster that non-synthetic

That '93 was the FASTEST color BTW

Your 1100 is a nice looking bike and the red paint looks good, however, a white 16 valve where you can see the black engine is even better.

bikerboy wrote:Your 1100 is a nice looking bike and the red paint looks good, however, a white 16 valve where you can see the black engine is even better.

I suppose like all good things in life, not all things are black and white......a bit like the French view [in some places] of white wine in black bottles.......

Me? I just love a good red.

You will never get a gummed up starter clutch with synthetic. I will always use it.
                                                 Ajays

I have been using 10W40 synthetic with no problems, I use the same oil in the cars as well and never had a problem. I just end up doing all the oil changes at the same time....feel like a grease mon K ey....

The comments about the starter clutch are well known too, AJAYS is right on that.

92KK K100LT 193214 wrote:I have been using 10W40 synthetic with no problems,

+1

No need for 5w oil unless running in cold conditions (winter), and no need for 50w unless running in high temperature (desert) conditions.

Synthetic oil molecules don't break down with wear, so one can run with it longer than conventional oil. I still change oil and filter every 5,000 mi. (8,000 km).

sugarhillctd wrote:How much oil does your K bike use?

Mine uses about 0,4 litres / 5000km. So not much I think.

I use MOBIL SUPER2000 10W-40 partially synthetic.

Plan to change the oil and filter at 10 000km intervals. 

For gear and transmission I use Mobil 80W-90 and planning to change 20 000km intervals.

I drive in conditions ranging from -2 to +30, but I will be always starting the engine from garage minimum of about +5 celcius. So I think 10W/40 is ok.

(EDIT: My ex Honda used about 0,7 litres / 1000km...)

Next time through the bike will be Nulon 20w50 super diesel engine oil and the gearbox and final drive will get the lsd85w140, neither will hurt the bike as it never gets cold enough here in the hunter valley to go thinner. heard of Hi tec oils its your home town company. They're Brisvagas based, hi-tecoils.com.au they show even a lithplex type product might be spline type, there's the usual radiator treatment products etc. Just like nulon you can use everything they have and get a report to us on how its feels. I have promised myself to go all Nulon just to see how it feels as its been around for centuries and a fine drop. I had used penrite before and its in there at present, hpr 40 or 50 I think, cant remember (cant remember yesterday for that matter) as the bottles gone. but its basicly 30w60 or there abouts, also workes fine. was chatting with rickmiester and Steve1959 last month about the same issue over coffee, (what to use)

While I agree that the 85w140 synthetic gear oil is the best that you can put in there, there is no way that I would put diesel oil in my petrol engined bike anymore than I would put petrol oil in my diesel engined car!
I thrust the oil companies scientists enough to know that they sell different oils for a reason. I also trust the API who have different specifications for diesel and petrol oil.
Can you explain why you think diesel oil should be better than petrol oil?

I believe Paul Glaves (one of THE K bike experts here in the U.S.) recommends nothing heavier than 90w in our final drives.

Been following that advice but does it really matter?

bikerboy wrote:While I agree that the 85w140 synthetic gear oil is the best that you can put in there, there is no way that I would put diesel oil in my petrol engined bike anymore than I would put petrol oil in my diesel engined car!
I thrust the oil companies scientists enough to know that they sell different oils for a reason. I also trust the API who have different specifications for diesel and petrol oil.
Can you explain why you think diesel oil should be better than petrol oil?

 

A lot of folk use Diesel oils because of the high detergents in the oil which help to keep things like the starter sprag clutch clean and being a seperate engine/gearbox unlike most other bikes you do not run the risk of clutch slip each to their own "me" I have used 10/40 Castrol GTX in mine which is what the local BMW dealer uses with no problems, mind I am not a seat of the pants rider so it gets an easy life.

BIG D

thanks Big D that's the reason for it, Bikerboy the panel on the bottle says its for diesel, compressed natural gas, liquid petrolium gas. the oil stops the metal parts from touching and the detergent shifts the sludge away or picks up everything and makes it sludge that sits in the sump like the normal one dont, either way its about cleaning away anything that can clag up the works so our bikes go for longer without being separated, 140 gearoil its about our turf being in summer for 9mth of the year and often heading for the mid 40's Centigrade that causes me to consider it. It may not be needed but like most things if it's in doubt get a bigger hammer.

Hi there.
Regarding the gearbox and final drive oil, BMW recommends 80W90, don't see why use anything heavier, unless you cant find it. I tried the synthetic on both gear and final drive and had to return to mineral due to seal leaks, think that if you change the old seals synthetic would be great.
Best regards
JAP

japuentes wrote:Hi there.
Regarding the gearbox and final drive oil, BMW recommends 80W90, don't see why use anything heavier, unless you cant find it. I tried the synthetic on both gear and final drive and had to return to mineral due to seal leaks, think that if you change the old seals synthetic would be great.
Best regards
JAP

BMW recommends 80w90 because that was all that was about in the '80s when the K was brought out. They also recommended some 20 year old tyre designs in my handbook, but I would prefer something more modern and better.
BMW gearboxes have always been a bit klunky - I know because I bought my first new BMW in 1977 and have owned many of them since. By using 85w140 and some moly in it, the present K has the most refined gearbox I have ever experienced on a BMW. Don't be mistaken into thinking that the 140 bit is thick, as it is probably the same thickness when hot as the 85 bit is when cold.
No need to change any seals as synthetic and mineral engine, and gear, oils are completely interchangeable, the reason for leaks when using synthetic in engines is that they tend to be thinner due to the superior lubricating properties, and then they can get past worn seals.

My 'new' K1100 engine in the sidecar is proving to be a bit of an oil junkie.  Not leaking, not smoking but it's use is excessive, more than any K I've previously had.  In 1000kms it has just gone from being at the top of the circle in the sight glass to being not visible.

This was using 10-40 synthetic diesel oil.  I'm changing it today to a good brand 20W-50 dino oil to see if that will settle it some.  It's all I ever used to use for years and those engines lasted for 100,000s of kms with no wear problems, there is no reason why it's not still good enough today.

Al

fender22 wrote:Whats the best engine oil to use in these? Synthetic or mineral?

Just buy a quality oil and change it regularly every 5000km and filter every 10000 ( I change oil & filter every 5000 but I'm probably a bit anal ) , I always use Castrol Power1 GPS 10/40 it's a part synthetic based oil. This is Castrols technical support number in Australia 1300557998.

I have been using Shell Helix oil for engines and their spirax for final drives on BMWs,  Kawasakis and any gearbox that I come near enough to service for 30 years or more and have never had a problem that I could attribute to lubrication failure.
Synthertic oil is a vastly over rated oil for use in a conventional engine and drive train and totally unnecessary.
Synthetic oil is good for use in very high performance engines where the heat generated will destroy a mineral base oil.  It does not lubricate better to any extent than the good quality mineral oil but will as said stand up to extreme temperatures which would more than likely destroy a K engine long before a lubrication failure happened.
If you use a synthetic oil for an engine in a ordinary road driven car/bike then you are throwing money down the drain.

Have used Comma, owned by ESSO I believe, 15/40 mineral oil suitable for petrol and diesel turbo engines for the last 20 odd years with no problems. Changed every 5,000 miles, filter every 10,000. I think the type of running and the temperatures the engine sees have a bigger effect on engine wear that what oil is used. 
As for clunky gear boxes, I have always found them very positive, the first time I road a BMW in the late 70's it reminded me of changing gear on a Colchester Student lathe just before the chuck stopped! John

i use castrol power 1 15/50 , since i talked to a BMW mechanic, he told me that the reason that BMW recommended the use of mineral oil ,was to break in the engine proberly,once broken in he told me to use the best oil i could affort, yes it is more expensive , but i ride 15000km between oil and filter change ,so i am not too worried about spending 500 DKK instead of 250 DKK ,twice a year.
BTW : my k uses  from the top to the middle off the glass in approx. 2500 km, and doesnt seem to go lower than that for a long time 

"Have used Comma, owned by ESSO I believe, 15/40 mineral oil suitable for petrol and diesel turbo engines for the last 20 odd years with no problems."
Oil design has come a long way in 20 years. As I said earlier, I would not use a 20 year old tyre design because technology improves. Synthetic is bang up to date and not much difference in price to semi so I use it.
I cannot understand the use of diesel oil in a petrol though, especially when most diesels only rev to around 4500rpm - a little less than a bike engine. My diesel car gets synthetic 5w30 changed every 15,000 miles as recommended by the manufacturer.

There cannot be a bike forum in existence that doesn't at some stage host a long thread about "what oil?"

Can sometimes be detrimental to an engine with some miles on it ,if diesel engine oil is used. Some of them are extremely detergent and will de carbonize an engine of its normal build up of carbon seal. ----Oil consumption goes up, found this out the hard way with an old Stewart Turner engine.

Gordon Smith wrote:Can sometimes be detrimental to an engine with some miles on it ,if diesel engine oil is used. Some of them are extremely detergent and will de carbonize an engine of its normal build up of carbon seal. ----Oil consumption goes up, found this out the hard way with an old Stewart Turner engine.

One has to be careful with older engines, if the oil is too thin it wont actually build up pressure and its the pressure that generates the separating film of oil between the metals. It also can get burnt because more of it gets to places it shouldn't, all as well as the loss of carbon seal too.

Tricky. One often used Castrol GTX or Duckhams in early Honda CB750 engines and they went on forever. I would not put one of these 10 or 5W40 oils in a very old engine, apart from viscosity they also have a lot more cleaning and detergent in them. Better to stick with the right one, particularly if you are in extreme conditions.

G'day Gordon Smith , a Stewart Turner eh , I had one of those , a P55M Marine engine in my boat when I was a kid , memories , sorry for the hijack

JR

Yes Bikerboy, a diesel engine does run at lower rpm but the turbo runs at one hell of a lick and its centre floating bearing relies on a good flow of oil to support it and keep it cool . Years ago I ran a Perkins V8.640 on a test bed full load rates speed and and grossly over fueled  for 24 hours none stop in an attempt to resolve a field problem. Both exhaust manifolds and 2 to 3 feet of the exhaust pipes were bright red. On engine strip the engine was in good order and run on thin Shell Rotela. It made me realise that the loads I put on my engine are giving no pain.  I use a similar oil in all my vehicles. John.

Rotax have just this morning brought out a service bulletin for the 912 series of aircraft engines. For those that don't know the engine it is a four cylinder four strike water cooled 100hp (in my case) engine. Being an aircraft engine there is quite a lot of information out there about what you should and should not use, and that information is being constantly updated as oils etc are developed.
One line from the latest service bulletin reads: "Avoid oils designed strictly for use in Diesel engines. These may not be suitable due to insufficient high temperature properties."
Should you want to read the full SB then it is at http://legacy.rotaxowner.com/si_tb_info/serviceinfo/si912i001r1.pdf.
@John. Living in Peterbro I would expect you to have had something to do with Perkins at some time in your life. Are they still as big a company as they were years ago?
Is Balderstones still going? I once drove past his shop on my way home while riding a brand new R1100S that I had bought from Northampton. He used to have a really bad reputation in those days.

Yes there still on the go but now owned by Caterpillar I believe. I left in 1988 for pastures new when it was owned by Massey Ferguson. It was an excellent 5 year Technician apprenticeship and have many happy memory's of my time there as a Draughtsman and later on mechanical engine development. 
Balderstones are still on the go but has moved from the old Lincoln Road site to new premises on an industrial estate. Have used them a couple of time but cannot touch Motobins on price. Battery for my K100 £60 or £150. Guess which was which. John

Turbochargers by their nature run at very high temperatures. In addition many turbocharged engines have an oil spray to the undersides of the pistons to dissipate heat. Poor oil and the turbo bearings may well be first thing to fail.

The oil as well as being a lubricant is also the primary coolant.

Many diesel oils are rated JASO MA which makes them fine for bike engines, even ones with a wet clutch. I like Penrite oils but that's just me.......

The oil as well as being a lubricant is also the primary coolant.

That's why we have finned sumps....

Oil may is certainly a major player in the game of cooling but I would dare say it is not the primary coolant, external fins or not. There's a heat exchanger out the front with a certain liquid mix circulating about which we would be wise not to forget. I read twenty years ago in the BMWRA mag 'OTL', that Motorrad magazine in Germany did a heat scan of our engines and determined they were a very thermally efficient engine, with a veritable rainbow of pretty colours to admire, signifying cool (blue) to warm (green/yellow) to very hot (red). The reds were mainly at the exhaust valves and piston crowns. Ain't much air near there.

I use mineral-based diesel oil in my K and have for many years and  kilometres. It doesn't leak or smoke upon start-up when leaned over on the sidestand, and is as clean as inside. Occasionally I'll use a standard mineral 15W- or 20W50 motorbike oil, perhaps at every third or fourth change, with a filter change as well.

That quote was regarding turbo diesel engines..

I agree not primary in our case, but also don't forget the little pump at the front, where oil heat can be shed to the coolant. This works both ways getting the oil up to temp faster, and then stopping it getting too hot....

Water transfers heat MUCH better than oil.  That's why your cooling system is filled with 60% water, not oil - both in your bike and in your car.

Even with engines the size of a brick a considerable amount of cooling i.e. removing heat from the engine to the surrounding air, is done by the oil as it circulates through the engine. I would hazzard a guess and say that figure is around 15% maybe up to 20%.  The cooling the oil does is one reason not to use powder coated engine covers as it stops the heat transfer from oil to the alloy covers then to air.

I doubt the engine covers play a signifcant or important role in cooling.  Take a look as the K1100RS faring.  They're buried in there and don't get much airflow.  The cooling system has a radiator, temp sensor and thermostat to keep the bike's operating temperature in the design range.

The bricks are well cooled via the radiator which has been designed with places like death valley in mind however that does not mean a large portion of the heat generated isn't radiated via the outer casings of the engine.
I have had a Z1300 (KZ in the US) Kawasaki since new and they do have a very marginal cooling system and that problem of powder coating the engine covers rears it's ugly head with them ever so often. Not so often now as there aren't many of them left on the road.

Ya, I tend to agree. With as much powder coating as seen on this forum one would think it there were a direct correlation the subject would have come-up by now. 

The radiator cooling system on the K100 is pretty well designed and tested. The fact that the fan doesn't even come on most of the time seems pretty remarkable.

I've had my fan come on only once in 60,000ks. It was because I was stuck in peal hour traffic.

Once I hit the open road, no worries, it "cooled" down to the normal running temp.

duck wrote:Water transfers heat MUCH better than oil.  That's why your cooling system is filled with 60% water, not oil - both in your bike and in your car.

I find it interesting that there is more fluid in the oil sump than the entire 'water cooling' system. Hmmm a bit like the oil cooled GSXR's. 

3.5l active oil and only 2.8l active coolant not flaming, just looking at the engineering.  

duck wrote:Water transfers heat MUCH better than oil. 

Sometimes, a lot of factors are involved, cavitation wetting ability and soforth

Let's just ride....

hi all  my question is this, can I use normal engine oil (car engine) since we have a dry clutch, is this a problem. I find the 4 stroke motorcycle oil to be more expensive than Shell helix X7 for instance.

your thoughts?

I use same oil in the cars and the K, as you say a dry clutch and separate transmission. Must check but think its a 10 or 15W40. Its not that I don't know, just cant remember. But the oil filter is same as quite a few cars [BMW and other makes] and can be bought cheaper. But, when you buy the filter for the K it comes with the o ring seal for the filter cover.

The oil used in car engines is just fine