CBF 1000 Oil Change

[BEZ1951]

Hi,
I've had my CBF 1000 for a year now doing 921 miles on it.
When I purchased it last April it had had a full service (they say)
I don't know what oil they used but as I have 4 litres of 10W-40 semi synthetic JASO MA Rock Oil unopened that I use for my 1982 cb650 sc-c sohc Nighthawk.
I wondered if I could use this oil in my CBF and if mixing it with 10W-30 would harm it.
I will do a full oil change but wonder if they are compatible.
BEZ

[Art]

Another engine oil thread 

For my two penn'orth here in the UK the 10W-40 will be perfect and a better choice multigrade over a 10W-30. Mixing the two will also be fine but why would you want too? You will find the dealers 'pre sales fully serviced by us' amounts to nothing more than a pre MOT inspection and fluids top up. If there is no detailed service history assume nothing.

My oil change weapons of choice are Motul's 5000 10W-40 and a Hiflo HF204 oil filter.

[Art]

Originally Posted by BEZ1951

I have 4 litres of 10W-40 semi synthetic JASO MA Rock Oil unopened...

Missed that bit, you'll only need 3L for an engine oil and filter change but how old is that unopened oil? Engine oil has a shelf life before the various additives start to break down at which point it's no longer what it says on the container. Typically engine oil will have, give or take a year or so, a 1 year in service life and a 2 to 3 year shelf stock life. Inspect the, as yet, 'unopened' engine oil before use, what you don't want to see is any dark coloured stringy residues laying in the bottom of the container, if its a dark container decant the oil to check for any laying residue.