It's occurred to me that I could instead use Halford's own fully synthetic 5W40 which, despite being a considerably higher spec oil on paper, is cheaper at £35 for 5L (£7/L) instead of £30 for 4L (£7.60/L). I do a fair few miles so this price difference is worth considering.
Firstly, Halford's own brand oils are made by Comma so I'm not too worried about the quality.
Secondly, before anyone jumps in with 'don't use fully synthetic, it'll cause clutch slip' - the oil in question is specifically stated as being suitable for wet clutches (see the photo of the bottle on the technical data sheet here http://www.commaoil.com/passenger-vehic ... s/view/271). I've also used the Castrol fully synthetic (Power1 Racing) a few times and never had any problems either.
So my question is, am I better off with a cheaper higher-spec oil than a more expensive lower-spec oil? Or, if these Halfords/Comma oils are totally fine should I even just use the semi-synthetic version which is £29 for 5L (£5.80/L)? This one is specified as API SG and JASO MA which as we know still meets the 'SE, SF or SG' specified by Honda.
However...I do take my bikes to the full 8,000 miles between oil and filter changes (bet that'll set the cat among the pigeons), which served me fine for 145,000 miles on the CB500 which spent most of its life between 6 and 9k rpm, and also hope to take my Firestorm over 100,000 (currently on 52,000).
And I guess the other question I'm asking is, just because a cheaper oil is given a certain rating, does its cheapness perhaps suggest that it will not keep this rating for as long as a more expensive oil? Or is the price difference likely to be just down to marketing/branding? In any case, surely the fully synthetic Halford's/Comma should hold its rating longer than any semi-synthetic?
Oh and the other thing is, I always have to buy a 1L bottle of oil to top up in between changes, so buying a 5L bottle, as the Halford's ones are, would be more convenient than the 4L Castrol bottles.
This isn't so much an urgent question (I've got 3,000 miles till my next oil change), more an invitation to another fascinating, chin-stroking oil discussion
Although I am also looking to save some money on what I see as a rather over-priced essential ingredient...
(£2.35/L)
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