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

[Lord Stig]

I used to use car oils, but I did get a slip, which I've put down to those friction additives (as Kymmy says, mostly Mo). For the last 80,000 or so (on the same bike) I've used car diesel oil, which is massively cheaper, doesn't contain friction modifiers and has more phosphorus. When you think about it the high compression diesels are far more testing for an oil than most cars, and especially our particular bike engines. It worked for me (and others - search the net), but whether you have the nerve to use it yourself is up to you...

[TRANSPORTER]

LORD STIG,, I have to agree with you , I myself am using halfords 10/40w semi snth diesel oil in my XR250R, If you look at the XR forum there is a thread on there titled XR4 oil consumption, Now this thread has a great debate on it at the moment about using diesel oils in bikes.
Ive had no problems using it so far no slippage or wear just good lubrication, changed regulary(damn cant spell).
Lets hear some more on this subject its interesting.

[Lord Stig]

Nice to hear that TRANSPORTER; it makes a lot more sense especially with proper off-roaders with smaller capacity oil reservoirs amd shorter service intervals. Any idea how many miles you're done with it so far?

[metamorph67]

I looked in my local Halfords, could find the Semi Synth but it didn't say it was a motorcycle oil, i will look on their site, the screwdriver set is a great tempter though! Lovely grippy handles for my DIY projects, i think i'l go for whatever gets me the drivers LOL! - metamorph67 Thanks for all your input all!

[POTSKI]

Hi All,

Been using 10/40 semi-synthetic diesel car oil for years in all my bikes, dry and wet clutch, Z1000, Guzzi Calis, CX 500's XT500's to my latest Transalps, high revers to plodders; never had the slightest problem. Having said that I am a stickler for regularly changing the oil in all my vehicles.

When I can get it here in the sticks I use Mobil 1 10/40 diesel and would like to use 15/50 when it's stinking hot like it was today, but can never find it.

Anyway, check these links out, food for thought?

Cheers

Potski

Testing Motorcycle Oil

All About Motor Oil

http://www.suzukicavalcade.com/Maintenance/oil_test.htm

[Lord Stig]

Some interesting reading there POTSKI. The phrase 'snake oil' would seem to fit what manufacturers are trying to sell to us in some sense, though the information about shear stresses in relation to the oil being run through our gearboxes suggests regular changes are more critical than in cars.

Reading around one of the links I found this which seems to be a major manufacturer condoning the use of diesel oils in bike engines - not what I'd expect!

[Zanzibar]

I've also driven myself madder about oil. I settled on Shell(?) Helix 10-40semi synth petrol car oil. I saw it mentioned on a US thread somewhere.

Seems ok - no clutch slip. It meets the SG (or SJ?) specs, and has a JASO spec on the can too. It's designed for 1997 engines also.

I can only hope and see wot's wot. I cant believe it will damage the engine - the clutch is the only issue but loads of guys use car oil it seems.