Calling all oil Guru's(mixing oil question) : Kawasaki ZX Forums: Kawasaki Ninja Forum

rrzxter · 08-29-2009, 07:53 AM

I used Shell Rotella-T 5w-40 full synth last oil change as did my buddy. Between the 2 bikes, I have almost 2 qts left. I wanted to try Mobil's 4T racing 10w-40 full synth but they only had 2 qts left. Any adverse effects if I were to mix the 2?

JKL1960 · 08-29-2009, 10:09 AM

I'm not an oil guru so this is my opinion on what you are doing.

I don't think mixing oils is a good thing though it may be fine. Mixing synthetics is probably riskier than mixing conventional oil.

It's always been my feeling that once you start with an oil you should stick with that same oil change after change. Again probably more important with synthetics. Trying different oils seems pointless to me. I seriously doubt that a rider could feel in the seat of his pants a difference between two oils unless one is causing fairly serious issues. I think an engine is happiest when it gets the same oil change, after change. I'd say stick to the Rotella.

There are lots of good oils available. Any bike specific oil from a known manufacturer will be fine. Pick one and stick to it. For me, with a high performance engine I figure if the jug says Motul (and it's the right application) it'll be fine.

Notice that most of this is based on "I think" and "my opinion" and should not be confused with anything scientific or guru-ific.

rrzxter · 08-29-2009, 04:41 PM

I haven't done it yet cuz I'm a little sceptical as to it being ok to do. Not really lookin for any performance gains. The Rotella-T is designed for deisel apps and although it's fine for the bike, I thought it might be better to used a bike-specific oil. The Rotella-t is already dark and smells of fuel and I put it in less than 1k mi ago. Not sure if it's the oil or if my rings didn't seat good cuz I babied it on break-in.

jah · 08-29-2009, 04:53 PM

mixing oil isnt a problem, these machines are for the street..things like these happen, i doubt the manufactures gave us machines that when oils get mixed they go to isht..

however, im not condoning doin it...

and i dont see why would u do such a thing..

just because you can ride a bike in the rain, doenst mean u should take a hose and shove it down the intake...

rrzxter · 08-29-2009, 08:04 PM

Quote:

Originally Posted by jah

mixing oil isnt a problem, these machines are for the street..things like these happen, i doubt the manufactures gave us machines that when oils get mixed they go to isht..

however, im not condoning doin it...

and i dont see why would u do such a thing..

just because you can ride a bike in the rain, doenst mean u should take a hose and shove it down the intake...

My thinking is that it's either a problem or it's not. Was looking for a little chemistry lesson cuz I like to know why either way. As far as "why" I would do it, It's in the first post- I have 2 qts left of the last oil I used and the only local place that carries the oil I want to switch to only had 2 qts in stock. So, should I waste the oil I have and wait till they get more 4T in? Or is it perfectly safe to mix 2 synths together. It's not something I'm doing as an experiment or for some mythical performance trick. Just didn't wanna waste 2 qts of oil. But if it's a bad idea, I won't do it. And I've riddin in the rain quite a few times without issue but never considered sticking the hose in the intake. Will I gain any HP?

jah · 08-30-2009, 11:55 AM

lol. if the oils are two entirely different types...like synthetic and or not synthetic...i wouldnt mix it.

rrzxter · 08-30-2009, 12:13 PM

I did a little reading and decided not to mix the 2. I'm not concerned about the oil being "dirty" so soon because oil for deisel engines darkens quickly. But I'm still a little concerned about the amount of fuel I smell in it. Still may not be an issue but I'm still investigating. It seems it's harmless to switch from dino to synth and back again if your engine is in good working order. But it might not be a good idea to mix 2 types of oil from 2 different manufacturers as they have different additive packages. Again, still investigating so keep the input coming. (both oils I have are full synth but from diff manfacturers).

zaneyzrex · 08-30-2009, 01:33 PM

IMHO no worries... never had a problem in all my years of riding mixing oils... synthetic w/ dino, dino w/ synthetic, synthetic w/ synthetic, etc.... ur call...

Hammerhead · 08-30-2009, 08:26 PM

Quote:

Originally Posted by jah

lol. if the oils are two entirely different types...like synthetic and or not synthetic...i wouldnt mix it.

What do you think synthetic blend is?

synoil1 · 09-02-2009, 09:13 AM

The synthetic manufacturer should be able to guide you on mixing the two. In many cases it is not a problem.

rrzxter · 09-02-2009, 09:25 AM

I dug deep and spent another $20 on 2 more qts of Mobil1 4T. It's a much better oil than the Rotella 5w40 (blue jug). And I sent out for a test sample kit from Blackstone to test the Rotella I had in there. I'm a little concerned about my rings with the excessive fuel smell in the oil. Hopefully it's nothing. Moral of the story is: spend the extra cash now for better products or spend a lot of extra cash in the future for repairs.