Why mineral oil or doesn't it matter?

[Warthog]

I've read several times on threads here that for GS that is still being run in, ie 2 million miles on the clock or less, its good to use mineral oil over semi-synthetic.....Why??

I'm happy with semi so far on all my bikes, but considering the cost of this bad boy, I want to do good by my new beemer and give the motah the best care possible before I rev the t!ts off it...

My R1150GS has done a little under 8500miles and I checked the receipt from the dealer that confirmed they had changed the oil and filled with Castrol GPS (Castrol website states this is semi synth), so when a top up is needed I'll use the Motul 5100 I have sitting around. But should I swap to mineral at the next oil change (I'll probably do a change at 3000 after the last service) and if so should the dealer be made aware to avoid mixing semi and mineral or should I sod all that and go for extra virgin olive oil, or even a nice vinaigrette??

Help...I'm getting a headache..

 

[Tarka]

Put simply,there is less 'friction' when using semi-synthetic or fully synthetic oil rather than mineral.
Therefore,mineral is used in at least the initial 6000 miles to assist proper bedding in of all the components.

Personally,I`d rather change my engine oil quite often (at 3000 mile intervals) so I always use mineral oil - Castrol GP .

 

[Warthog]

Does mixing mineral and semi (ie filling up with mineral after having drained out the semi and no filter change) have any undesirable affects? Because, if so, if the dealer is putting in fresh semi every 6000 and I'm putting in a load of mineral at 3000 in between, its going to be a head ache... Any precautions if I choose to follow this option?

Incase your wondering: having just bought the bike, I need dealer services the first year to benefit from the used warranty...

 

[Tarka]

Draining semi or fully synthetic then adding mineral isn`t exactly 'mixing', but I take your point.

I`m not totally sure...some may say that the synthetic sort of 'coats' or 'impregnates' components...some may say that it won`t.

Why not contact the oil manufacturer`s technical department ?

And why don`t you instruct the dealer`s workshop to only use mineral oil ???

 

[Wizard]

Synthetic oil will impregnate cork clutch plates. Since we don't have a wet clutch, the change should have little or no effect providing the correct spec. of oil is replaced regularly.

All IMHO, of course.

 

[Warthog]

Why not contact the oil manufacturer`s technical department ?

And why don`t you instruct the dealer`s workshop to only use mineral oil ???

Former: tis a good idea.
Latter: tis a fair point.

Wizard: very reassuring, methinks a mineral oilchange at 11500 is in order.

 

[pomm001]

Put simply,there is less 'friction' when using semi-synthetic or fully synthetic oil rather than mineral.

Thats quite a sweeping statement !
I am very simple, but dont understand synthetic automatically means there will be less friction

 

[xpi0t0s]

Seems little point changing the oil... It doesn't leak out so presumably it's burnt by the engine. Since you stuff another x hundred ccs of oil in every few hundred miles, what's the point of explicitly changing it, since it's effectively getting constantly renewed anyway?

 

[Mouse]

Contaminants that are not burnt will build up in the oil, for one thing.

The filter will eventually become clogged (less quickly with a dry clutch bike though), so that'll need changing too.

 

[longdog]

You could take a look here or better still, here