Motor oil - Synthetic or mineral?

[fret not]

OK, so the Castrol Syntec isn't really a synthetic, but it works about like it is.  So what does that mean to us?  As far as we end users are concerned does it make any difference?  Does one cause wet clutches to slip and the other not? 

It sounds to me the big fight is all corporate wrangling about marketing, what words can be used to label a product, not how well either works in our motorcycles.  Is that about right?

By the way Ken, thanks for the view into the world of lubrication.  What are you using?

[Rick G]

Unless its a motorcycle specific oil, which contains the proper levels of ZDDP, I won't use it  ! Synthetic or not!  Synthetics  can occasionally cause clutch slippage , it depends on the brand of bike and the condition of the clutch. Suzuki's are very sensitive to the type of oil, Yamaha's  not so much.  Even Shell Rotella T has much reduced ZDDP . The stuff you get in the auto parts store  is CJ7  , what you need is CJ1 , for diesel trucks made prior to 2007 . You won;t find it at Auto Zone . maybe  at a truck repair facility?

[Rikugun]

Fret, I'd say it's more important to do regular oil changes than worry about which is best. Having said that, some offer more protection that others. I'ts more than an argument over marketing but rather the resultant quality of the lubricant and subsequent engine protection based on it's ingredients. From what I've read Mobil 1 is better than Syntec (and the price reflects that), and AMSOIL is better than both and it's price reflects that as well. And finally, I've broken a promise I made to myself about getting sucked into these interweb arguments over which oil is better....   :(  :)

[HarryTakeuchi]

I've broken a promise I made to myself about getting sucked into these interweb arguments over which oil is better....   :(  :)

Seems like I opened up a can of worms here. I saw it happen elsewere when you start talking about oil.

What I basically wanted to know is if the XZ gaskets hold synthetics or it will cause leaks. From what I have seen from all the replies I guess I would have to conclude it is more oil specific rather than a mineral / synthetic issue, though it does seem that the seepage does not occur with mineral oil, just on SOME synthetics.

I have used synthetic on more modern bikes and I know they work great but I don't want to have to do a crankcase overhaul to fix a leak and so as far as my XZ is concerned I decided it will stay on mineral oil.

Thanks guys for sharing your experiences.

[motoracer8]

 Pepsi or Coke, the debate will probbably never end. I was in the oil business for 15 years for a blender that made Torco and many other brands of oils for the motorcycle and performance industry. Because we were small compared to Chevron, Shell, Valvolene and others we could make small batches of some exotic mixes and make money. The big guys had to have volume or there was no proffit.

We made 2 stroke, 4 stroke engine oil, chain lube, fork oil and gear lube for almost everyone in the motorcycle business except HD.

No it was not all the same but some of it was the Torco product with a different color added, some we added alittle perfume, same product but it had a different odor.  We made product for one of our direct competitors. It was like a custom cake mix, theres more than one way to make a chocolate cake.

I dont get into oil debates as it's pointless. I wrote a page for the British car people some years ago about flat tappets and cast iron camshafts in regard to zinc and phosprous levels and the lack of it in modern motor oils, I was just stating the facts. I got more hate mail about this brand of oil or that brand and I had no idea what I was talking about and I never referenced to any brand.

Any motor oil with 1200 ppm of Zinc or above will be ok for your motorcycle. As they reduce the zinc load cariers they put other slipery stuff in the mix and that will sometimes make the clutches slip on older bikes.

Many new bikes come with cats on them now so Zinc levels even in product made for motorcycles has reduced Zinc levels.

  Ken G

[Rick G]

Torco is good stuff , ir smells like walnuts!

[fret not]

Such a slippery subject, what with conjecture and opinions and all.  And the industry has changed the letter codes, made new categories, and now I don't know what to use in my poor old vintage classic Japanese motorcycle.

[Rikugun]

Thanks motoracer, nice summation!  :) 

Harry, just my opinion but I don't think leaking will be a significant factor in your oil choice, use what ever you feel is best, can afford, feel comfortable with etc. I don't think any oil will start an oil leak. If an existing oil leak becomes intolerable after changing oils, I'd think it was time the leak was addressed anyway!  Just my 2 cents.  :)

[Rick G]

Fret, try Suzuki 10 40 , its reasonably priced , available and has all the stuff that's good  for Vintage bikes (or cars for that matter.)

[fret not]

Thanks, Rick.

[Kenny]

  I won't use any thing but Synthetics in my V's , I also use Motul's  ester base oil. - One of the Biggest Reasons is Stator Life !  I just fried my first at 110,090 klm's.
   Cheers Ken S. :-*   

[treedragon]

Hehe....... cat meet pigeon    ;D  ;D  ;D  ;D