Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

Using car engine oil instead of motorcycle engine oil

Discussion in 'Technical and Troubleshooting Torque' started by vxt, Jan 22, 2010.

  1. Hi

    Just wondering will car engine oil damage my gpx250 engine? because I'm going to change the engine oil and I have 2L of car engine oil thats is sitting around and I don't know what to do with it.

  2. No No No !
    Do not use car oil in your beloved bike ! You will stuff it.
    Pour it on some garden weeds instead.
    Buy some proper motorbike oil. Praise Jesus !
  3. haha X 2!

    oils ain't oils!!!
  4. Do a search. A lot of folks are using mixed fleet diesel oil.
  5. Go for it man. As long as it's got plenty of friction modifiers you'll be fine,.
  6. QW, you're a bad man. [-X
  7. What grade of car oil? I wouldn't use 20/50 in most Japanese bike engines unless specifically OK'd in the manual. 10/40 or 15/40 would generally be OK though.

    The other aspect is the API rating. Somewhere on the can will be a marking that looks something like CF/SJ. It's the S bit of this that's of interest on a petrol engine (S for Spark ignition). Most commonly available car oils are SH, SJ or SL these days. Some spectacularly cheap ones are still SG and I seem to remember seeing the odd SM, but those three cover most of what you'll find. I'd be reluctant to use SG in anything, but anything from SH onwards is likely to be fine.

    Given those conditions, the only way car oil is likely to harm your bike engine is by some of the anti-friction additives possibly causing clutch slip (the clutch and gearbox share the engine oil). This is unlikely, based on (possibly outdated) personal experience, but if it does occur, may require a change of clutch plates (not a huge deal) and a return to motorcycle oil to cure it.

    There is nothing magical about oil with a picture of a motorcycle on the can. Engine longevity is much more dependent on regular oil and filter changes than any other single factor.
  8. The GPX / ZZR 250 manual recommends 10/40 but says to use an appropriate viscosity for the conditions, including 10/50 and 20/50. I've used 20/50 for 8000 km during summer because I spend a lot of time cooking my bike on Punt Rd / Hoddle St.

    I'm currently using Penrite HPR GAS 10/50 semi-synthetic car fleet oil which costs $8 per litre. I personally can't be stuffed spending $16 per litre on Motul 5100 semi-synthetic motorcycle oil.

    If you are unsure whether your oil has friction modifiers in it, log on to the oil manufacturer's Australian website, find their email address for inquiries, and ask. I got a response within 1hr from Penrite on the issue.
  9. OMG....here we go again.

    Use the bloody search, please, please please.
  10. Search, and you'll find many threads of long argument on here, as with any bike forum when this is raised. I use standard automative oil, have done for a long while and never had a problem, so I cry nonsense (at least with regard to modern oil - see some studies of this on the web). I change oil about every 6 - 8 weeks, and with automative oil that's made quite affordable. It's so cheap, however, and your bike so precious, that I'd use good stuff and not use a cheap half bottle just because I had it sitting there.
  11. How bloody ridiculous.
    Your car has engine and gearbox oil. Most bikes the one oil does both. If it does then thats why you use a bike oil. Why would you risk an expensive rebuild for a few lousy bucks.
    Get a push bike and dont worry about it
  12. thx for all the great advice. The engine oil I have is 20/50 and its cheap quality so I guess its better to spend abit of money and get proper bike oil.
  13. This happened to me.

    I like the idea of using car oils, the price disparity between car and bike oils is a bit XXXTREME, especially when I'm only running it in low spec, understressed bike engines. But I couldn't find reliable info on brands worth using.
  14. My Mini shared oil between the engine and gearbox, and reved it's nuts off quite happily with GTX in it.

    The reason there would seem to be so much discussion is that because there is precious little information from the oil companies about what each mix contains...
  15. There's a famous thread somewhere about a professor with a cruiser who ran his bike on bike oil and then car oil and did vicscosity and other analysis to test what's what. I had it saved on a lappy that has now gone to B&E heaven... but the basic argument is that MC oil resists shearing from the gears - the gears in a typical MC gearbox are engaged at all times and the theory goes that they accelerate oil breakdown.
  16. All the more reason to be super-paranoid about oil change intervals. Which you can be with car oil 'cos it's so cheap.
  17. Most oils are semi synthetic these days. Which is to say they are part oil, part heat beads and part detergent.
    Car oils have a lot of detergents in them and few heat beads. If your car gets up around say 100c it's going to be running very very hot.
    But your bike is happy to run all day at that and higher. Most bike fans don't cut in till 105c. Your bike does not really like the detergent because of the finer tollerances of a motorcycle motor. But it needs lots and lots of heat beads.
    Running car oil will save you nothing really because you will have to change it at such regular intervals that the cheaper purchase price will be lost by the frequency of your changes. @ $17 onwards for filter as well that should be changed at the same time your way behind the eight ball.
    Just a little sider to add to that is if your bike is new and under warrenty. If you do the oil changes yourself and don't have some sort of an agreement with your dearlers service manager you will void your warrenty.
    Goes like this. You come in because your motor or whatever is making a strange noise. Me being mr service manager has a look at it and says ok. I ring mr Tech if I am in Kawasaki dealer I will ring mr tech at Kawasaki. ( hi pete ) He will ask me for the vin. He says ok sounds strange if it is not a common fault. He then asks for the service history. I say it ha no official dealer stamps besides his first one. He knocks the job on the head. I have had to do this to two people and they hated my guts for it. Yes they probably did a better job than the monkey out the back and it cost them 110% less. but mr motor cycle maker is going to leave you high and dry.
  18. The oil debate's been rehashed a hundred thousand times on bike forums, no need for us to rehearse the script here.
  19. I think you'll find that's illegal ,as long as there's a service history at the correct times it doesn't matter where it's done...
  20. Nope. Sorry it's not. Google the ACCC act of 2005 on servicing. Sorry tired and just got what you meant. Yes any approved service center service will be covered not just the dealers. But you yourself cannot. I use to slide it by for guys I knew who bought their oils and filters from me. But if the bikes like 9 or twelve months old and there is not an official stamp with dates and signed in the books. Then it's up to Mr tech who I have to ring to get approval for the job. It's not up to the dealer.
    most dealers will soak up a lot of the labour for the punter of they want to keep them but thats up to them.