Difference between bike and car engine oil?

[Benbay001]

Id like to service my Dullville.
The bike needs 10w-40, of which i have loads of good quality fully synthetic sat in my garage from my old MR2.
Is this any good?

Thank you.

[Hooli]

Oh can of worms time!

Some will say yes, some will say no.

The additive packs are different to help the oil survive in the gearbox & to prevent it causing clutch slip.

[crofty1984]

On a fairly low-stress engine I'd have no problem putting your standard car oil in. Id' think twice if it was some highly-strung sportsbike though. Can't say I've had any problem doing so on my Honda (after asking the Honda servicing people about it and having their blessing).

[black-k1]

I'm no expert but I understand that some of the additives in good quality fully synthetic car oil buggers up a wet clutch.

[3DP]

Bike oil has more resistance to shear and losing its grade due to the specific forces involved in being used in the gearbox. It's also not got the 'slippy' additives that cause wet clutches to slip. Otherwise no real difference.

Given the cost difference is nil, why would you want to put car oil in a bike?

[fergus]

3DP said:

Bike oil has more resistance to shear and losing its grade due to the specific forces involved in being used in the gearbox. It's also not got the 'slippy' additives that cause wet clutches to slip. Otherwise no real difference.

+1

If your bike has a separate g/box (i.e. does not share the engine oil), car oil will be fine in the engine.

[podman]

Id never do it however a good friend of mine has run his bikes on car oil for years, his VFR800 has covered around 30,000 on car oil now, he's never had any problems with it but as I say, I wouldnt consider it..

[Benbay001]

3DP said:

Given the cost difference is nil, why would you want to put car oil in a bike?

Because i have £50 worth of car oil of the same viscosity sat doing nothing. Seems like a waste to buy more just for a 9000rpm engine.
But if as people say there are adatives that can effect the clutch and gearbox then i will buy some bike specific oil.

[J B L]

Benbay001 said:

3DP said:

Given the cost difference is nil, why would you want to put car oil in a bike?

Because i have £50 worth of car oil of the same viscosity sat doing nothing. Seems like a waste to buy more just for a 9000rpm engine.
But if as people say there are adatives that can effect the clutch and gearbox then i will buy some bike specific oil.

Do it.

I saw a GSXR Srad that's been run on car oil for 50,000 miles going round the Alps and back without problem. Once you've used up your car oil, revert to motorbike one and you'll never think about it again.

I assume the Deauville's not used on track and rarely sees its red line?

[conkerman]

I believe most modern car oils now have moly free friction modifiers.

I'd still look for JASO MA1 or 2 on the pack though.

[thatdude]

The issue surrounds any friction reducing additives that interfere with the clutch plates, themselves bathed in the same oil that feeds the engine and gearbox.

It might accelerate wear on the clutch plates. Look for the JASO MA standards.

[Benbay001]

J B L said:

I assume the Deauville's not used on track

right

J B L said:

and rarely sees its red line?

wrong

[Mr2Mike]

Benbay001 said:

Because i have £50 worth of car oil of the same viscosity sat doing nothing. Seems like a waste to buy more just for a 9000rpm engine.
But if as people say there are adatives that can effect the clutch and gearbox then i will buy some bike specific oil.

Check the API logo on the packaging:



"Energy conserving" means it has friction modifiers that could cause clutch slip.

[pozi]

J B L said:

Do it.

I saw a GSXR Srad that's been run on car oil for 50,000 miles going round the Alps and back without problem. Once you've used up your car oil, revert to motorbike one and you'll never think about it again.

I assume the Deauville's not used on track and rarely sees its red line?

Would this be the same GSXR600 that burns oil and makes anybody following it feel ill from the fumes

[rev-erend]

I believe a lot of bikes have wet clutches and don't like fully synthetics.

[750turbo]

rev-erend said:

I believe a lot of bikes have wet clutches and don't like fully synthetics.

Yep - My old thing does not like it - Mineral only.

[3DP]

J B L said:

Benbay001 said:

3DP said:

Given the cost difference is nil, why would you want to put car oil in a bike?

Because i have £50 worth of car oil of the same viscosity sat doing nothing. Seems like a waste to buy more just for a 9000rpm engine.
But if as people say there are adatives that can effect the clutch and gearbox then i will buy some bike specific oil.

Do it.

I saw a GSXR Srad that's been run on car oil for 50,000 miles going round the Alps and back without problem. Once you've used up your car oil, revert to motorbike one and you'll never think about it again.

I assume the Deauville's not used on track and rarely sees its red line?

In fairness - that GSXR smoked so badly it made you feel sick to follow it and Stu was scared to rev it in case it blew up. I've also personally lunched a 1 year old ZX6R's clutch by using fully synth car oil in a bike in the late 90s. It used to slip over bumps over heavy load and by the time I worked out what caused it, I'd killed the clutch, negating any economy.

If it's in a commuter, that's not thrashed and changed regularly, I can't see the harm, but I wouldn't want to be putting it into anything I care about or thrash!

[smack]

3DP said:

J B L said:

Benbay001 said:

3DP said:

Given the cost difference is nil, why would you want to put car oil in a bike?

Because i have £50 worth of car oil of the same viscosity sat doing nothing. Seems like a waste to buy more just for a 9000rpm engine.
But if as people say there are adatives that can effect the clutch and gearbox then i will buy some bike specific oil.

Do it.

I saw a GSXR Srad that's been run on car oil for 50,000 miles going round the Alps and back without problem. Once you've used up your car oil, revert to motorbike one and you'll never think about it again.

I assume the Deauville's not used on track and rarely sees its red line?

In fairness - that GSXR smoked so badly it made you feel sick to follow it and Stu was scared to rev it in case it blew up. I've also personally lunched a 1 year old ZX6R's clutch by using fully synth car oil in a bike in the late 90s. It used to slip over bumps over heavy load and by the time I worked out what caused it, I'd killed the clutch, negating any economy.

If it's in a commuter, that's not thrashed and changed regularly, I can't see the harm, but I wouldn't want to be putting it into anything I care about or thrash!

Hey, it started smoking at 35k when it was running on bike oil!!! Now it just drinks a little more these days. I use Part Synthetic since that is what one of my car uses (burns). If you remember that I wasn't on the gas as I had other things on my mind, not that I was worried about the engine....

[3DP]

smack said:

3DP said:

J B L said:

Benbay001 said:

3DP said:

Given the cost difference is nil, why would you want to put car oil in a bike?

Because i have £50 worth of car oil of the same viscosity sat doing nothing. Seems like a waste to buy more just for a 9000rpm engine.
But if as people say there are adatives that can effect the clutch and gearbox then i will buy some bike specific oil.

Do it.

I saw a GSXR Srad that's been run on car oil for 50,000 miles going round the Alps and back without problem. Once you've used up your car oil, revert to motorbike one and you'll never think about it again.

I assume the Deauville's not used on track and rarely sees its red line?

In fairness - that GSXR smoked so badly it made you feel sick to follow it and Stu was scared to rev it in case it blew up. I've also personally lunched a 1 year old ZX6R's clutch by using fully synth car oil in a bike in the late 90s. It used to slip over bumps over heavy load and by the time I worked out what caused it, I'd killed the clutch, negating any economy.

If it's in a commuter, that's not thrashed and changed regularly, I can't see the harm, but I wouldn't want to be putting it into anything I care about or thrash!

Hey, it started smoking at 35k when it was running on bike oil!!! Now it just drinks a little more these days. I use Part Synthetic since that is what one of my car uses (burns). If you remember that I wasn't on the gas as my mind was somewhere else at the time, not that I was worried about the engine....

Agreed - but you did also say you were a bit worried about revving it up due to wear/smoke! The GSXR has done well, but that's not a healthy engine...

[J B L]

3DP said:

smack said:

3DP said:

J B L said:

Benbay001 said:

3DP said:

Given the cost difference is nil, why would you want to put car oil in a bike?

Because i have £50 worth of car oil of the same viscosity sat doing nothing. Seems like a waste to buy more just for a 9000rpm engine.
But if as people say there are adatives that can effect the clutch and gearbox then i will buy some bike specific oil.

Do it.

I saw a GSXR Srad that's been run on car oil for 50,000 miles going round the Alps and back without problem. Once you've used up your car oil, revert to motorbike one and you'll never think about it again.

I assume the Deauville's not used on track and rarely sees its red line?

In fairness - that GSXR smoked so badly it made you feel sick to follow it and Stu was scared to rev it in case it blew up. I've also personally lunched a 1 year old ZX6R's clutch by using fully synth car oil in a bike in the late 90s. It used to slip over bumps over heavy load and by the time I worked out what caused it, I'd killed the clutch, negating any economy.

If it's in a commuter, that's not thrashed and changed regularly, I can't see the harm, but I wouldn't want to be putting it into anything I care about or thrash!

Hey, it started smoking at 35k when it was running on bike oil!!! Now it just drinks a little more these days. I use Part Synthetic since that is what one of my car uses (burns). If you remember that I wasn't on the gas as my mind was somewhere else at the time, not that I was worried about the engine....

Agreed - but you did also say you were a bit worried about revving it up due to wear/smoke! The GSXR has done well, but that's not a healthy engine...

It's worth notting that this bike has never seen a spanner in its life. I suspect the sump plug is fused to the sump by now.

Go on OP ! Go 50/50 bike/car oil...