Mike Daytona600 wrote:Don't forget you can't use car oil in a bike cos of the wet clutch.
really ? you'd better tell that to every bike I've ever owned ........ except my Ducati Darmah which was run on a very specific single grade oil as recommended especially for the bevel drive at vast expense ........ and that blew its big ends twice in three years

change to a 10/40 car oil and all was fine for another two years ('til it did it yet again

)
A lot of rubbish is talked about oil, but the one constant is that it's not the cost / type of oil used, as much as the frequency with which it is changed. A cheap oil changed at half interval will provide more protection than the most expensive at double the time ...... In the past I've used a cheapish car oil (Comma Eurolite 10/40) and changed at 2000 mile intervals with pattern filters. As my mileage has dropped, I now use a mid-price castrol oil and change it when I think of it or do something that nudges me ... but that often means around 1500 miles or so, and on occasions maybe even just a few hundred.
Look at the back of the can - as long as it meets the minimum spec of the bike you can't go far wrong ... I think SH or SJ are the latest standards
The one thing I would agree with is to avoid fully synthetics unless they are bike specific as they do seem to give wet clutches trouble

Amd I would also qualify the above by saying for
road bikes rather than track machines ....