Advice please: Bike oils, Car oils?

**aum108** · 6th February 2012, 10:47

Hi all,

I'm wondering if some of you mechanically skilled folks could please set me right on the issue of what oil to use in a (4 stroke) motorbike.

I've managed to get totally confused by all the contradictory opinions on the net, and would like to pull back and get some local wisdom.

At the moment, I have 15W40 (mineral) car oil in the bike, but at first opportunity (next payday) will be replacing it with something more suitable to the bike, which is a Yamaha XV250 Virago, v-twin air-cooled.

Currently the bike is clutch-dragging, more so when cold. The drag is enough to stall the motor sometimes when I put it out of neutral into 1st gear when cold (with clutch fully pulled in). Could this be partly or totally due to the oil?

Is car oil ALWAYS BAD for bikes? Or are there specific types of car oil to avoid?

What specifically is the danger of using (certain types of) car oil in bikes? Some folks mention "clutch damage". What are the specifics of this?

What oil is best for my Virago 250? The manuals say SAE 20W40 (warm climates) or 10W30 (cold climates). But some Virago owners reckon 10W40 is great.

Are the motorbike oils from Super Cheap Auto ok? A couple of them are less than $20/litre.

And what about mineral versus synth versus semi-synth? What should I look out for here?

Lastly, can oil choice affect fuel economy and power?

Thanks for your patience and help.

Cheers
David

**MSTRS:Me** · 6th February 2012, 12:03

Only advice I can give is use a 4T oil. Find out what Yamaha recommend as to 10/30 - 10/40 - 20/50 - whatever, and find a 4T (motorcycle only) oil that suits your budget. Do not use fully synthetic, as your Virago wasn't designed with it in mind.
Clutch drag is more likely to be caused by poor adjustment, rather than oil. Car oils tend to make m/c clutches slip.

PS - I have heard a rumour that diesel engine oils are fine in 4 stroke bikes - but can't confirm if this is so.

**blackdog** · 6th February 2012, 12:08

Nah it's only a 250. Just use recycled oil outta yer deep fryer will be fine.

**FJRider** · 6th February 2012, 12:31

Any oil is better than no oil ...

But .... car oils have an anti-friction agent (which sounds good) which make clutches slip. The unknowing try to adjust the clutch to stop the slipping ... which results in the clutch not releasing.

To simply replace the engine oil is not the quick fix. Clutch plates may need to be replaced. On-going clutch problems/issues if you dont.

Diesel oil has been used on older bikes ... a cheap option.

BUT dont use car oil. Things just go bad. FAST. You WONT save money using it. If you cant afford motorcycle oil, you cant afford the repair bill ...

**pritch** · 6th February 2012, 12:34

This can get soooo complicated. Stick with a motorcycle specific oil in a grade recommended by the manufacturer though and it can be simple.

If the choice is 20/40 or 10/30, neither will damage the bike. The 20/40 may make the bike run a degree or two hotter, give a fraction of a horsepower less, but it might make the gear changes smoother.

The only disadvantage of a motorcycle specific oil that comes to mind is that they are not normally available at service stations, but then you hopefully won't need to make any unplanned purchases.

When you trade up to a bigger bike it could pay to revisit the question, but the simple advice would still be to use a motorcycle specific oil in the grade and weight recommended by the manufacturer.

Oh, and I'm not sure that buying the cheapest oil you can find is the best policy?

**spanner spinner** · 6th February 2012, 13:36

In simple terms car oils are for cars bike oils for bikes. The big difference is that cars have separate gearboxes with there own oil so there oils are not designed to work with wet clutches or gears which cause them to break down fast and cause clutch problems when used in bikes as you have discovered. My recommendation would be a 10w40 semi synthetic motorcycle oil (i.e. motul 5100) super cheep does Castrol bike oils and will have one to suit, GPS would be my first pick.

**Woodman** · 6th February 2012, 17:15

The clutch dragging when cold may well be the viscosity and not necessarily the type of oil. You are using a 15w40 which is thicker than a 10w40 at ambient temperature and so on as the oil warms up therefore when the clutch plates squeeze together the thicker oil takes a bit longer to be squeezed out between the plates causing drag. Try a 10w40 and see what happens. My old xl600 had the same symptoms when running a 15w40 until I put the 10w40 in so this was the theory I came up with rightly or wrongly.

Car vs bike oils? use bike oils as it saves way too many meaningless conversations about car vs bike oils. Interestingly Penrite state on a few of their car oils that they are also recommended for motorcycles.

**cowpoos** · 6th February 2012, 17:48

Originally Posted by spanner spinner

In simple terms car oils are for cars bike oils for bikes.

This is the best advice....get bike Oil....its different for a reason!

**Flip** · 6th February 2012, 18:40

Firstly there is no specification for bike oils. The SAE (socioety of automotive engineers) have never produced one. All the bike makers simply tell you to use a good quality car oil, I might suggest they know best.

There have not been any friction modified engine oils available for ages, the boundary lubricants polute catalitic converters.

All quality motor oils have dual petrol Sx and diesel Cx ratings. Oils after SG are "low ash" and compatible with cats from memory oils after SH are energy efficient as well.

The only issues with std automotive oils in bikes is the VI (viscosity index) addative, which looks like gorilla snot and is the stringy chemical that makes a 20 weight base stock oil behave like a 40 weight oil when itis hot (ie 20W40) is chopped up by the gear boxes in bikes. Its not shear stable. As the oil ages it thins when it is hot and the gear boxes get notchy, thats why new oil always feels better in the box and why oil change intervals will always be closer in bikes than in cars.

I am a great fan of commercial mixed fleet oils, bulk 10-20 litre packs save me money and my vehicles get more oil chages. I run the same 15W40 Valvolene mixed fleet lube in all my vehicles.

The most important thing is that the oil has a high S rating, SG is good. What the 15W40 numbers means is the oil viscosity behaves like a 15 weight oil at 40 deg C and a 40 weight oil at 100 deg C. There is fuck all diference between a 15W40 and a 20W50 one, they are both fine for use in New Zealand. All motor oils are missible in an emergency, one of the SAE requirements is that they can mix, but if you mix a 30W40 with Mobil 1 the oil you now have is no better than 30W40

Don't ever buy a oil with a flash holographic label or in some fancy bottle, you are wasting your money. Don't buy an oil that you can't get at your local service station.

Get your clutch adjusted it does not sound to me like a oil problem to me.

Read this....... http://www.dansmc.com/mc_repaircourse.htm

**cowpoos** · 6th February 2012, 19:40

Originally Posted by Flip

All the bike makers simply tell you to use a good quality car oil, I might suggest they know best.

Bull shit...why come on to a thread like this and mis inform people?? read a bike owners manual sometime!

**Flip** · 6th February 2012, 20:26

Originally Posted by cowpoos

Bull shit...why come on to a thread like this and mis inform people?? read a bike owners manual sometime!

Because there are oil makers and retailers out there making "specialty" lubricants, that comply with no standard or specification, charging a premium price for an untested and unproven snake oil product. They seem to have got their expensive products into the motorcycle retailers who are hocking it off to people who know no better.

Which part do you think is bull shit cow poos?

**aum108** · 6th February 2012, 20:32

Thanks for the advice guys.
Well, I finally bought some Castrol 4T 10W40 semi-synth, but now the oil drain bung bolt won't budge.
Crap time of day to be lacking an 18mm socket or ring spanner! :/
Always tomorrow I guess.

**mossy1200** · 6th February 2012, 20:36

supercheap has castrol for bikes or bike shops motul.Sure it 60-70 instead of 40 bucks but clutch pack costs more than the price difference.Get that bike hot drain it filter it.If that doesnt solve it order clutch gasket tilt bike and strip clean clutch keeping everything in the correct order.Maybe soak plates in the correct oil over night and reasemble.

**cowpoos** · 6th February 2012, 20:37

Originally Posted by Flip

Because there are oil makers and retailers out there making "specialty" lubricants, that comply with no standard or specification, charging a premium price for an untested and unproven snake oil product. They seem to have got their expensive products into the motorcycle retailers who are hocking it off to people who know no better.

Which part do you think is bull shit cow poos?

your conspiracy theories sound like shit to me actually...

Now let me see...would I stick oil ....designed for a engine reving say 5-6 thou RPM in my four cyclinder bike engine designed to rev 12-13 thou RPM?? no...heard about the initial excess wear on high reving single four stroke MX engines using normal bike oils??? problem was solved with specilty oils!! go figure...

don't mis inform people...but I expect you so come back and talk more shit...coz your a name calling type with ego issuses.....take soon....ciao

**mossy1200** · 6th February 2012, 20:46

Originally Posted by cowpoos

your conspiracy theories sound like shit to me actually...

Now let me see...would I stick oil ....designed for a engine reving say 5-6 thou RPM in my four cyclinder bike engine designed to rev 12-13 thou RPM?? no...heard about the initial excess wear on high reving single four stroke MX engines using normal bike oils??? problem was solved with specilty oils!! go figure...

don't mis inform people...but I expect you so come back and talk more shit...coz your a name calling type with ego issuses.....take soon....ciao

+1 this is his motorbike not the neighbour you dont likes weedeater that wakes you up on Sunday morning at 7am.