Oil: Mineral or Semi Synth.

Rod

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Seems that the bike arrives with mineral oil. At the 600 mile service they put in Castrol GPS (Semi Synth). Isn't this too soon to start using a semi Synth oil. I thought you should use mineral oil up to about 6000 miles?
What are your views please.......
 
Don't know anything specifically about the 1200, but for everything else I've ever heard of this is too soon.
generally about 6k, 1150 anything up to 24k.
 
My dealer recommended Castrol GTX High Mileage which i believe is a mineral oil
 
Rod said:
Seems that the bike arrives with mineral oil. At the 600 mile service they put in Castrol GPS (Semi Synth). Isn't this too soon to start using a semi Synth oil. I thought you should use mineral oil up to about 6000 miles?
What are your views please.......

Most opinion seems to be that a longer time on straight mineral oil would be better, but I have not seen the evidence published to support it. Though I do not doubt the sincerety of others with long experience on their earlier generation gs variants etc.

Racers run their motors on the dyno for a few pulls to full power and check the ring blow by to eatablish all is settled. So 600 miles maybe ok for a sensibly run in motor.

Page 171 of the 12gs book tells us to use API class SFD,SG or SH etc.and does not mention mineral/synthetic/semi syn. And the reason is that all of these oils will do the job very well indeed in our lowly stressed motors. If you like synthetics and are happy to give loads of cash to the oil companies it will not hurt. Just realise that they are gouging us--in the USA full synthetic motor oil is about US$4 per US quart(0.96 litres as I recall)and Castrol GTX less than US$2.

I have run a Porche 3.2 litre 6 cylinder horizontally opposed air and oil cooled Carrera producing about 260+BHP at 6500RPM on synthetic and /or mineral oil for 15+years, and for ten of those years at anything up to 160mph on a daily basis to and from my office(60 to 100k each way) on the autobahn. It now has about 245k kilometres on the clock and uses a little oil but not enough to warrant a rebuild.
It has used Castrol GTX 20-50w for at least the last five years and I cannot distinguish any change in performance/noise levels etc during that time from when it ran on Mobil 1. And it will still probably blow the doors off my 12gs on uncongested roads over anything but a short hop.

Being less than bothered about this, and knowing that all the different oils can be mixed without any difficulty, I did not ask what the dealer put in at the 600 mile service.
 
Mine has been run on semi since new... cos the dealer (Astles of GY) told me to keep an eye on the oil when i told them that i would prob reach 750 miles b4 i could get it in for service... obviously I asked ...

"If i have to top up.. wot's init!??" .. semi synth 10/40
 
Just to confuse matters my dealer(Clarks of Brum) told me they are using Shell Advance mineral in the 1200GS as a matter of routine once past the 600 mile service.
 
It's amazing that all BMW dealers use differant oils, I would have thought that there was a BMW standard from the factory.
I think I'm going to have my oil changed at the end of the first days ride, put in mineral oil and have the 600 mile service done at 1000 miles at least. I wonder what the dealer will say when I book an oil & filter change after 100 miles & insist on re-filling with Casrtol GP.
 
Rod said:
It's amazing that all BMW dealers use differant oils, I would have thought that there was a BMW standard from the factory.
I think I'm going to have my oil changed at the end of the first days ride, put in mineral oil and have the 600 mile service done at 1000 miles at least. I wonder what the dealer will say when I book an oil & filter change after 100 miles & insist on re-filling with Casrtol GP.

That you are a very good customer.
 
Is synthetic oil more slippery than mineral oil or is it that synthetic oils just stay slippery longer?

Greg
 
not sure about the slippery differance between mineral & synthetic, but engines bed in better with mineral oil.
 
Consumption

Rod said:
STIG, how many miles have you done now, how is the oil consumption ??

Just over 3700 at last look.... oil consumption is acceptable... IMHO

Since first service @750ish.. I i've only topped it up twice wi about 200 ml each time. ... So roughly 400/500ml per 3K ish.. Can't remember wot it says in the spec tho!... must go away and check on that :eek:


But.. this is measured against my XR which has always burnt a wee bit more than that. ... btw.. also run on semi.
 
Castrol GP is a motorcycle specific oil, which may be necessary if the clutch is wet and shares the engine oil. As these boxer engines have a seperate and dry clutch there is no need to pay out the extra for special motorcycle oil. A good quality general auto oil meeting the BMW recommended specs is fine. One thing to consider though is that these engines are oil/air cooled and may run a bit hotter than than water cooled engines so it may be beneficial to use an oil with a combined petrol/diesel engine spec; eg; API sh/cg-- the 'S' part relates to petrol engines, 'h' to the level to which the oil is tested,more modern oils are rated higher eg; SG, SH, SJ, with SL I think being the most recent spec.
Diesel engine oils are designated with the prefix 'C', with the test spec given for example as E, F, G, so you may have an oil rated CG as being a fairly high modern spec.
Heat is a major factor in breaking down the viscosity of oil, a synthetic oil is more resistant to heat and will keep it's grade longer than mineral oil, but i suspect that if you change your mineral oil as per BMW's reccommendation then you should not have any problems. I feel the use of full synthetic is just a form of extra insurance. I use Rock oil semi synthetic in both of my BMWs and my harley.
 
fatal said:
Heat is a major factor in breaking down the viscosity of oil, a synthetic oil is more resistant to heat and will keep it's grade longer than mineral oil, but i suspect that if you change your mineral oil as per BMW's reccommendation then you should not have any problems. I feel the use of full synthetic is just a form of extra insurance. I use Rock oil semi synthetic in both of my BMWs and my harley.

That's exactly why I use fully synth in mine. As an engine without the temperature stabilisation of water cooling and, indeed, using the oil as a medium to throw heat in to (before it is lost at the oil/air intercooler), viscosity control is particularly important.

I'm not convinced that synth is any more slippery than mineral. If it isn't, why not use it from Day 1?

Greg
 
Greg Masters said:
That's exactly why I use fully synth in mine. As an engine without the temperature stabilisation of water cooling and, indeed, using the oil as a medium to throw heat in to (before it is lost at the oil/air intercooler), viscosity control is particularly important.

I'm not convinced that synth is any more slippery than mineral. If it isn't, why not use it from Day 1?

Greg

I do not find additional insurance, either on electronics(extended expensive policy)or on BMW motors which specify a certain range of use in our normal environment, is warranted. They specify the oils acceptable, and if the motor fails outside of the warranty due to poor design workmanship or materials etc I will ensure that BM rectify. That is the law.
 


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