OIL - Why can't i use a good spec motor oil?

[metamorph67]

Metamorph67 - FMX650 - has the world gone mad or am i really thick, why is it that us bikers have to pay twice the price for oil just because its for a bike. I'm bewildered looking at the choice of good spec motor oils in Halfords, they're all for cars, but my bikes engine is a dinosaur anyway having been designed about 25 years ago. So someone please tell me why it wouldn,t be better for my engine if i changed the oil more frequently with a good spec 10/40 marketed for a car rather than making an expensive two liter bottle of motorcycle oil last until the next scheduled service. I know all about how shearing forces breakdown oil quickly and how our bike engines share the oil with our gearboxes, but so do a lot of modern car engines. Help! Am i missing something?

[Knobblywobbly]

It´s a problem with the anti-friction additives in car oil contaminating the friction plates in our bikes wet clutches, causing them to slip (at least this is what I believe).

I buy my oil from Hein Gericke at around £14 for 4 litres, so not overly expensive.

[metamorph67]

Thanks Knobbly, Ofcourse! Your right , thanks for that, but does that mean that our oil doesn't do such a good job at metal to metal contact lubrication, like shearing on bearing surfaces and bushes? I,m so glad i posted this thread as i could of ended up overlooking the obvious as you have pointed out, one last ting, can you send me a link to that oil supply of yours?:

[Knobblywobbly]

It´s probably not as good, but good enough for what we need. And as we usually change it more often than you would in a car then we should be ok with it. As a friend of mine always says "Change your oil often; oil is cheap, engines aren´t".

Hein Gericke (UK) Ltd. for the oil.

[Lumiya]

Molybdenum Disulfate is the main problem, it eats through wet clutches friction material (not a problem on a car)

If you can find an oil without that (all bike oils and some car oils) then you're fine.. Also remember that not all bike engines ae designed to use Synthetic oils and run a lot better on mineral

[Steve C]

Molybdenum Disulfate is the main problem, it eats through wet clutches friction material (not a problem on a car)

If you can find an oil without that (all bike oils and some car oils) then you're fine.. Also remember that not all bike engines ae designed to use Synthetic oils and run a lot better on mineral

Such as the old tractor engine I have in my AT?

[stubbow]

I use Halfords 10w40 semi synthetic motorcycle oil in my bikes with no problems 5 litres for £23 and you get a free set of Halfords Pro screwdrivers(rrp 19.99) at the moment
Danny

[jpc]

Clutch slip due to the additives seemed to affect these clutches for some reason.

[metamorph67]

metamorph67- thank you to all of you that posted comments to my thread, and thankyou for the detail, i remember sticking castrol GTX in my small bikes when i was 17 and had no problem, thank you Stubbow for chucking that Halfords oil in yours, i'm sure it will be alright, i expect some friction materials are more susceptible than others and all depends on how much strain is on your clutch, how you ride and stuff.

Thanks JPC & Knobbly for your input.

Kymmy,thanks for the detail, i will take note of that, i only plod around on the FMX but it is my baby and i am in empathy with its moans and groans! Thank you all!

[Daz Max]

I use Halfords 10w40 semi synthetic motorcycle oil in my bikes with no problems 5 litres for £23 and you get a free set of Halfords Pro screwdrivers(rrp 19.99) at the moment
Danny

Just got the same.
Though the bike oil wasn't mentioned in the promo,I just picked them off the display and plonked them on the counter.damn good set of screwdrivers too.......