Engine oil weights & running temps

[Brian d marge]

I usually use Silkolene,these are ester based synthetics - esters were developed to lube jet engines,they can handle far more heat than other oils.They also cling to metal,make cold starts no problem.But I have no lost my trade accounts,and Fuchs no longer bring in Silkolene,only 3 litres left of my stocks.

Fuchs have been a byatch to deal with here , I did get a few replies back , but as much use as a choco teapot I want an ether based semi ,,to

I also use diesel oils - the stuff I use is long life stuff,able to go over 70,000km between changes.Diesel oils have a similar additive package to motorcycle oils,and them some.Most are rated for Allison transmissions,so no worries with wet clutches.

Yup I use a diesel oil before i do a filter change ..lot more detergents higher loadings etc

Oil threads are a lot of fun - but whatever the views,in 37 years working on engines,I've never seen one fail because the oil wasn't up to the job.Any damn oil changed regually is good enough for any engine

I just did the first oil change on me truck ,,, 20 000 km , the only reason I did that was because I found some old stock in me warehouse ...

Stephen

[Grinner]

I also use diesel oils - the stuff I use is long life stuff,able to go over 70,000km between changes.Diesel oils have a similar additive package to motorcycle oils,and them some.Most are rated for Allison transmissions,so no worries with wet clutches.

Yup I use a diesel oil before i do a filter change ..lot more detergents higher loadings etc

Both not quite true. Diesel oils generally do have a greater percentage of additive however the extra additive is of no use to a motorbike.
The extra additive is either detergent, for suspending the soot produced from burning diesel or calcium used to counteract the sulphuric acid produced from burning fuel with a high sulphur content.
Modern motorbikes run on petrol, they do not produce soot nor is there any sulphur in petrol.
Motorbike oil are designed for motorbikes. Diesel oil are designed for diesel engines.

Cheers Gerrard

[Conquiztador]

Many years ago I travelled in Oz. Picked up a cheep DR500, did some maintenance and off I went. Did the oil change and had oil with me (no idea what I could find so I decided to have my own in the outbacks). The motor was far from new, but not badly worn. As I travelled up north the summer really hit. +40 celsius was normal. I kept the oil topped up and I thought she was happy. But she got really noisy. I got to Darvin and pulled down the motor. Really badly worn cams and followers. My 10-40 oil had not managed to do its job in the heat.

So from this I learnt that if riding in the heat it is worth changing to a oil that is made for the job.

[Brian d marge]

"I also use diesel oils - the stuff I use is long life stuff,able to go over 70,000km between changes.Diesel oils have a similar additive package to motorcycle oils,and them some.Most are rated for Allison transmissions,so no worries with wet clutches.

Yup I use a diesel oil before i do a filter change ..lot more detergents higher loadings etc "

Both not quite true. Diesel oils generally do have a greater percentage of additive however the extra additive is of no use to a motorbike.
The extra additive is either detergent, for suspending the soot produced from burning diesel or calcium used to counteract the sulphuric acid produced from burning fuel with a high sulphur content.
Modern motorbikes run on petrol, they do not produce soot nor is there any sulphur in petrol.
Motorbike oil are designed for motorbikes. Diesel oil are designed for diesel engines.

Cheers Gerrard

both quite true , they tend to have a higher film strength and yes while the additive are designed for a diesil engine , they do contain more detergents

Which is what I said , and wanted
Stephen

[Motu]

Check the API ratings on oils - they usually have both S and C ratings.There are really no ''car'',motorcycle'' or ''diesel'' oils.There are other ratings besides SAE and API - motorcycle oils will have a JASO rating and another very good standard is ACEA....each manufacturer will have what they consider a standard to be passed.Some engines are not recomended to use later upgraded standards.All gets very very confusing,which is why oil threads get so heated.

[Grinner]

API has been around for ages and is the most commonly used. It has both C for commercial (ie diesel) engine ratings and S for petrol engines. They get updated with a new version every couple of years.
So far as I know the only motorbike specific rating is done by JASO ( JASO T903) The main feature is that they require the oil to have a certain level of Phosorous ( an EP Additive ) and I think they also stipulate a high shear rate. These are required because the oils lubricate the transmission as well as the engine.
I note however that my bike ( 2002 ) only stipulates an API rating. Wether newer bikes also include a recommended JASO rating I dont Know. JASO has only been around for 5-10 yrs.

[avgas]

get as far apart with ya numbers (eg 5w 50) as this offers you the best of both world.
i did, and it turned a lumpy part fucked engine to a purring lurvly little motor.

[The Stranger:Me]

get as far apart with ya numbers (eg 5w 50) as this offers you the best of both world.
i did, and it turned a lumpy part fucked engine to a purring lurvly little motor.

Fine for a synthetic oil, which a 5w50 almost certainly would be.
But if you are using a dino oil you would generally want the opposite. A 10w40 uses a 10 weight base oil and additives to achieve the 40 value. It is the aditive package which breaks down, so in the end you are left with a 10 weight oil. A 15w40 has less additive to break down, will do so slower and you will be left with a better weight oil when it eventually does.

Trade off of course is slower flow on start up.

Also it should be noted that most oils labelled semi synthetic are simply dino oils. The semi synthetic part they are referring to is the additive package, which is the part that breaks down.

[EroSamnin]

Also it should be noted that most oils labelled semi synthetic are simply dino oils. The semi synthetic part they are referring to is the additive package, which is the part that breaks down.

I would agree with that! When I change the oil on my bike with Castrol GPS "synthetic based" oil, it smells unlike dino oil, has a nice smell. When I let it out again in 4-5000km, it smells just like normal oil plus that used oil smell. Must be all the synthetic bits breaking down into nothing. If its synthetic "based" though you would think there would be more of it in there being the base oil?I dunno, I'll leave it to the smart guys.

[speedpro]

I was worried about this years ago so fitted a temp gauge to the oil gallery where it fed the block and head on a '74 Z1. I was amazed how long it took the oil to warm up and for the temp to more or less stabilise, generally about 3 miles of riding, after warming the engine. On a hot day and thrashing it got way too hot so I fitted an oil cooler which helped, but then it took longer to warm up which wasn't good when doing short trips so I made a little alloy plate to cover the cooler for those short trips. On the McIntosh the motor gets REALLY hot. After making lots of calls to lots of petrochemical engineer type people I ended up using Mobil 1. The one time I didn't I ended up with minor galling on the little ends in the rods.

If you really need to know how hot the oil is getting just go and buy a VDO temp gauge and mount the sender in an oil gallery end plug or into a fitting. Just make sure it doesn'y restrict the flow.

[scumdog]

Hmmm, my '66 Ford Thunderbird has a non-functional oil guage, a lack of oil pressure knowledge has not stopped the 390 ( 6.7 litre) engine from staying alive.

Sorry about the thread 'hi-jack'.

[speedpro]

A 390, unless bored or stroked from that capacity, does not equal 6.7L. (highjack)

[scumdog]

A 390, unless bored or stroked from that capacity, does not equal 6.7L. (highjack)

I guess you're right about the '6.7L - it was a guess.

But 6.7L is not the limit for a 390.

A crank, a bore-out and piston change will give you 7+ litres.

Back on track: Us HD riders have the luck that we can get a replacement dip-stick that incorporates a temperature guage, reassuring to see that the engine is NOT about Chernobyll after a bit of a work-out, mind you, they are an understressed engine from the factory.

[Pancakes]

Hahahahahah Scummy, is "understressed from the factory" the sales brochure term for "really low power from such a big engine?" heheh hehehehe

Nah, jokes. Thats a flippin good idea actually.

AVGAS; get as far apart with ya numbers (eg 5w 50) as this offers you the best of both world.
i did, and it turned a lumpy part fucked engine to a purring lurvly little motor.

Yeah, oil is single weight, the wider the operational range the more stuff in there thats not oil, since there must be a minimum oil % of total volume, the wider the range the less detergents and the more deposits on the internals.

MOTU; There are really no ''car'',motorcycle'' or ''diesel'' oils.

Exactly, and they all have rubbish catch phrases on the back, you may as well rate oil by vehicle compression ratio. I mean, "for older vehicles" like an Escort Lynx/Cosworth engine or a Clevo'? New cars? An S2000 or a Camry?

[Pancakes]

ALSO,

When a 5w goes down to -10 ambient temp (or whatever that chart said it was) having oil too thick on start-up shouldn't be an issue (but might need the choke on the cold mornings), oil filters have a by-pass that would be open for a while anyhow.