Did someone say OIL Debate?

[jasonm.]

A long time ago before these starburst oils. About 1988 on my Suzi GS1100GK slipped when I used Mobil 1 15w50. This was a shaft drive touring bike.  The solution was just to put barnett clutch springs in. The stockers were weak. Never slipped again with any oil.

[Leather]

Mobile 1 or Amsoil synthetic.   GREAT!

[louthepou]

Hi there everyone,

Not that I think that there are not enough replies about this subject already, but I thought I may offer a different perspective.

First, the grade; Yamaha's engineers designed every part of the Vision engine assuming it was going to bathe in 10w40 most of the time. Stick with the reccommended grades (according to ambient temperature - can't remember the options; 20w40? other?, check owner's manual), no matter what type of oil you decide to use (synthetic or not).

Second, the main argument put forward by oil companies tryin to sell motorcycle-specific oil is the following: In many bikes (mostly japs), the engine oil also lubricates the transmission. The shearing pressures of the gears is a lot greater than anything encountered on the engine side. Hence, the need for an oil especially designed to face this shearing.

Fine. Let's look at all that, shall we. The greater "shearing" does indeed exist, and it does have an impact on the oil; il reduces it's viscosity. Mineral oils resits poorly here. I've read some studies (I hate to say that, it is a scientifically weak statement; but I did read a few articles on the subject, I can't remember where, plus this is a bike forum, not a Thesis review board so I shall continue) that essentially stated, after independent lab results, that any synthetic oil (for bikes OR cars) was by far resisting the loss of viscosity due to shearing way better than any mineral oil (even those having additives making them "better for bikes").

I'm still not entirely convinced about all of this. There may be some truth to the bike oil makers claim that their motorcycle-specific additives actually make their oil perform better. One thing I'm trusting, though, is that I never put anything but synthetic oil in all my engines, bike or car or truck. (OK not my wood chipper, but the day may come). I've seen in may engines the LONG TERM difference between those treated with synthetic and those without.

Make your engine parts happy, use the right grade of synthetic oil. If you must stick to mineral based oils, my advice is: use a brand claiming it's for bikes, and change it often - every 1,000 or 1,500 miles. That being my humble opinion.

That's all for now,

Louis

[Rick G]

we have discussed all this before , the word is that they have left out the (I believe ) the zink which prevents  bearing wear on cold startup , from car oils . the feds felt too much  was being put into the atmosphere.  The word was that racing and MC engines  would still need  the additives . Still ,I 'm using mobil synthic 15 50.  Oils have changed since the visions engineers made their recommendations   so I wouldn't hold those as gospel, besides we used castrol or torco 20 W 50 long before the factorys made any recommendition about it.

[RBFD415]

Well I did the oil and filter- changed to the Yamalube- it occured to me that I had put automotive type oil in last time- having read the postings here I became aware of my error, ref the "wet clutch" and proper motorcycle oil.

Anyway- the bike shifts better-  I don't notice much difference in the clutch action, but as I said the shifting action is improved!

Now I see a very slight weeping oil leak from the right-outside engine cover, where the big screwdriver style slot is. If I had changed to the synthentic (like I was going to do) I would have blamed the synthetic oil for the leak?! Is this a typical leak for the Vision? I don't think it was weeping here before.

[Rick G]

Try  GENTLY tightening the case screws a bit  and see if it stops.

[louthepou]

Rick's right putting the emphasis on "gently". Spending some money on a good torque wrench isn't a bad idea. Anyone remembers the torque spec for the 5mm allen bolts in the Vision's aluminium threads?

Now, a little oil leaking from a Vision engine is pretty standard stuff, even if anoying.

Mind you, Yamaha still has in stock most of the o-rings and gaskets (some $$$, some not too much) so if retightening doesn't stop the leak, and the leak is more serious than your driveway's tolerance for oil, there's that option. Better change a gasket than have to redo thread.

[Lucky]

By "screwdriver slot" i'm assuming you mean the round access plug. this plug is palstic so NEVER use a screwdriver on it, instead get a very large washer from the hardware store, and use it with knuckle busters to unscrew that plug. there is an o-ring on the plug that you can get at any hardware store. that will stop the leak.

--Lucky