Crankcase oil

Sorry if this has been asked 1000 times, but I was wondering what crankcase oil is the best to use on a 1985 wr 250... Thanks everyone!

I use ATF - F the ford borg warner auto oil, works good and its cheeep.
Briggs and Stratton 20 wt is popular, Belray gearsaver is ok $$$ but.
There is a "tractor fluid" in the USA that I don't know the details of but a lot of guys use it over there... and its dirt cheap.

You're right this topic has been beat to death so heres my two cents to beat it to death even further.

The tractor oil suprize mentioned is GL-5 gear oil. Its 6 dollars a qt. at Autozone. http://www.autozone.com/autozone/ac...W-90-32-oz/_/N-25t1?itemIdentifier=373225_0_0_

Those of you who enjoy reading technical jargon can find information on GL-5 here: http://www.lubrizol.com/DrivelineAdditives/AutomotiveGearOil/GL5.html

Theres always a concern when using an oil not designated for a wet clutch application but you'll find the information provided at the above Lubrizol link mentions limited slip differentials as an application for GL-5 gear oil.

Hope you find this helpful!

i tried using some hydraulic tractor oil from napa..seemed like it was just the ticket as it was a tad thicker than atf...it made my clutch slip horribly in my 84 250 i was trying it in.

I'm not surprised your clutch slipped. Hydraulic fluid has additives to prevent components from sticking such as in the operation of a hydraulic ram.

back to atf and it was ok after a few flushes

We use M1 0W40. It's clutch safe, cheap and works like ATF, but doesn't thin when really hot.

I've had good luck after switching to Shell Rotella T 15w-40. This weight is the only one of the Rotella T's that is certified JASO-MA -- which is the wet clutch spec. Cheap and super available compared to the Amsoil, Mobil 1, and Redline I've run in the past. I never liked ATF fluid myself. A gallon jug on sale at the autoparts store (it goes on sale quite a bit), is about $13 (that's $2.60 a change at 750ml). Smells awful and is cloudy before it goes in, so it screws up smelling if it's burnt or to see if it's dirty.

Rotella T6 is Jaso MA rated, though many oils are completely wet clutch safe without the rating. It is a great oil, very close to 0W40 in spec.

All you need for oil is to not see Energy or Resource Conserving in the API label on the back of the container. I use synthetic oil exclusively in my Road Star and that has a very wet clutch.

dont use this stuff!
anything i have thats not a 2 stroke i use jaso-ma oil..for instamce. i use 20w50 amsoil mc oil in my zrx..the 2 cycle have no pump or filter and is a bit special.....im sticking with type f in it from now on. the atf type f does make it shift like nothing else

ive got atf -f in both my husky and 2010 ktm 300 exc and have had no issues so far. the shifting is a little softer in my opinion and both bikes always complete those desperate wild stabs at the lever near the top of the hill when you just need 1st to get over the top cos its died in 2nd and its a loooong way down....and your already half off the side hopping along....

have you been running atf long enough suprize that you feel confident about it being fine for your gears and bearings?
on a side note i fired my bike up today with the new kit from from phillip containing steel clutch plates and the clutch works AWESOME..no lurch putting it in gear, i can put it in first and roll it backwards just as easy as neutral..

Re: Using Type F ATF
It's all I have used in 2 stroke trans/clutches for 40 years.
My 74 125 WR has over 10,000 hard trail/enduro miles on it. The crank has been rebuilt...it's now bored out to .060 over...but the original trans and all clutch parts are still in use.
I also use it in primary chain/clutch cases of vintage Brit bikes that I restore...and ride.

Are there better oils for this purpose? Perhaps...
But I'll stick with proven success.

i also try to remind myself many car manual trans differentials and truck manual trans also spec it..thanks for the long term insight richard

about two years now so not a real long term test.... but the testimonial above certainly suggests no long term issues

Thanks everyone for the great info !

Have used synthetic ATF in all 2T transmissions on like 15 bikes since '96, as advised to help a poor performing KTM 300 at the time. It helped, and I saw later in old KTM manuals that ATF was spec'd as an option back in the day. I've had many of these motors apart too--no ill effects...even on a '97 KTM 200 I still have with probably 500 hours, have never even replaced the original clutch plates. But the Euros do make them tough!

Hi everybody,
I'm using Mobil Delvac MX 15W40 for some time now, a lot of hours in my Yamaha WR450F and also in a CRF250X, and now my Husky WR300.
I'm happy with that oil and pretty sure the protection it offers is quite good. The only downside I see with it is some clutch drag specially at startup when the oil is still cold. I have to accelerate yo avoid stalling it and it makes an CLACK noise putting first gear in... Once warmed up this will become much better.

So I'm at the point of wanting to try something of a lower viscosity, I came across this Tractor Transmission oil in a agri-shop:

Specs: http://flcf.onion.it/commonfile/ENG/pdf/3646_stec_ENG.pdf
Datasheet: http://flcf.onion.it/commonfile/ENG/pdf/3646_scat_ENG.pdf

So, the GL4 spec. makes me think that it will offer good protection for the gears and the compatibility with wet brakes makes me think it will be ok for wet clutch also ?

By he other hand, a 20W30 is more viscous than a 15W40 in cold so my problem could be se same or worse, but once warmed up should be better maybe...

Have not found much information about this tractor transmission fluids out there regarding the use in bike transmissions...



What I have found is a lot of people using the ATF, I have used it too but some expensive Esso Synthetic Dexron III (same price as bike specific stuff), it worked good in my GASGAS EC250 but gave too much gear noises in a KTM EXC250 and we flushed it after the first test ride. I think the viscosity was too thin for this bike... I think the type F ATF is more apropiate being more viscous ?

Regards.

the type f is the go...just that bit tougher than the normal atf