OIL you know black gold

if that were true why not put standard engine oil in the rear differential of your truck or car?
or even in your manual transmission?
The heaver viscoscity is available

do all you guys run auto oil in the hypoid gear boxes?

better safe than sorry for me I spend a lot of money on internal engine parts. thx.

A number of automotive manual transmissions use auto trans fluid, does that count?

Why are you comparing lubricant for hypoid gears with engine oil, I don't know of any hypoid gears in a KZ motor.

Even my Kawasaki Factory Service Manuals specify SAE Class oils, not a word in there about "Motorcycle specific".

Don't believe the tripe put out by the Marketing departments

OK... you're right-- I'm wrong. I'll give my Enginering degree back.

would you like fries with that today??

Ummm in MHO its what the manufactuer recomends.. and last time I looked in my owners manuel it said 10w40.
As to reducing oil shear , oil temp is the real killer of lubs.. the higher the temp the lower the protection.
so why not try puting an oil cooler in and removing that factor? Had a lockhart on mine for about twenty years, and still have a leakdown at factory spects. I change it every 3k. new filter and oil. So, there. Thats my two cents worth.

how about all those kenworths and other big trucks running the highways,many of them run 20w50 in the transmissions because they shift better.im no engineer but i know plenty of truck drivers and heavy equipment mechanics .

I think waiting for 3k to change oil is asking for trouble. If you spent that much time inside the crankcase yourself you wouldnt come out the same as you went in. Unless your special.

www.amsoil.com/lit/g2156.pdf
here is a link that has some good reading about M/C oil.

I know car oil is better than no oil.

look at the gear wear in the photos.

you be the judge
your bike
your oil
your transmission
your repair bill
I know what I use I know my opinion is not popular

I run my oil 5-7K between changes and swap filters twice in that distance/time

Post edited by: trippivot, at: 2006/07/16 16:33

My bike was running on semi synthetic up until last summer when I switched to Castrol Syntec 100% synthetic. A couple of minor oil weeps have now become actual small leaks and I do blame it on the synthetic. Main thing I noticed is the clutch is much smoother (Barnett) and the transmission shifts smoother. Wear?...nothing I can "feel" and the oil comes out quite clean at change time. Also in the fall and spring, the synthetic doesn't thicken as much as mineral oil in the colder weather so I have easier starting and less start up wear.

Getting back to the first post, steam (water vapor) is a huge percentage of the byproducts of combustion. There is always steam being pumped through the crankcase due to blow-by, so there is always water vapor in the crankcase, and it condenses every time the motor cools.

The colder it is outside, the more water vapor condenses. If it's really cold, like below 40 F,and your bike doesn't warm up all the way, there can be continuous condensation while you ride. The bike must get pretty warm to boil all of the water out of the oil (but water vapor will never be completely out of the crankcase).

If you ride for 20 minutes on a hot day, the oil should clear right up.


I've used Castrol car oil in bikes for many years and have never had a problem. I've also used motorcycle oil (Kawasaki and Spectrol) and the oil comes out the same as the Castrol. There is no more metal coming out with either type of oil. (No, I'm not talking about chunks of metal, but the grey film in the old oil as it comes out.) The only thing that's worrisome is the newer classifications for "environmental" oils, if they are somehow thinner.

Never Quaker State, though!

Post edited by: loudhvx, at: 2006/07/21 12:26

I like the Castrol oil from Crappy Tire. I used to run synthetic in my 650. Synthetics resist heat better so I fugured an old air cooled motor would do fine with it. Never had any problems.

In sunny CA, we can ride year-round.
I use Castrol 10W/40 in the winter, and 20W/50 in the summer.

Castrol 20w50, all the time, no problems

1045