Tranney oil.

Regular automotive oils contain friction reducing additives that can cause problems for motorcycle clutches. Use a motorcycle specific oil.

Search there is a lot of debates on oil. Motorcycle specific, or stuff that isn't "energy efficient" (it says in the little ratings circle). This will be an off grade oil, like Penzoil's
10w40 (most 10w30 has it)

Oils with friction modifiers meet the API SL/SM standards. Motorcycle oils meet SF/SG or SJ standards. It's marked on the bottle.

aside from using motorcycle specific oil, a synthetic will make a clutch slip slightly but {your average rider wont notice it}opposed to regular, but if your clutch is slipping excessivly you have an underlying problem, worn discs/plates.

76GMC1500 could you clear something up for me please. I was told that it is better to use ATF in a crank case, of a two stroke because the gear saver causes too much drag and ruins clutches. Please cast some of your wisdom upon this odd question.
Thank you

The truth is, they all work. I personally just run Hondalube GN4 10w40 or 20w50 because they cost only $4 a quart and I change my tranny oil a lot so that saves a lot of money.

I have run the Honda's HP 80-85w 2-stroke racing oil in all of my 2-strokes over the years and have never had clutch problems ever. And I have friends that have run BelRay 80w Gear Saver with no ill effects either.

hot125mod said:

76GMC1500 could you clear something up for me please. I was told that it is better to use ATF in a crank case, of a two stroke because the gear saver causes too much drag and ruins clutches. Please cast some of your wisdom upon this odd question.
Thank you

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80W Gear oil (Bel Ray Gear Saver) is just a hare thicker than ATF. If someone used 80W Hypoid gear oil (as used in differentials) that stuff is thick and would cause issues.

An 80w oil, hypoid or not, would be significantly thicker than ATF which I believe measures in somewhere around a 7w. As for the difference between a 10w30 and a 10w40, it's unlikely you'll notice much of a difference as they are both a 10w oil. The first number, the viscosity, is measured at 100 degrees C. So, a 10w30 and a 10w40 at 100 degrees C are both going to have the same viscosity. As the temperature increases, the viscosity of the 10w40 will decrease less per unit of temperature increase. However, since most of our 2-stroke transmissions spend most of their life pretty close to 100 degrees C, a 10w30 and a 10w40 will have roughly the same viscosity during normal operating conditions.

Yes, filing the clutch basket if it is notched may help with your problem. You should remove the right side cover and inspect the clutch. It's not very hard to do.

The use of synthetic oil did not effect the clutch action. Nor does it effect it any more than conventional organic oils do.
You more than likely need a new clutch pack and springs.

And using an EC rated oil is not going to hose up your clutch, not like the wifes tales would have you believe. If you did use a "hypoid" type oil, then it could hose up the clutch action, as hypoid gear oil most likely has molybdenum disulfide which can cause issues. Btw...so called "auto" and "diesel" oils do not contain this form of moly.

The thickness of the oil has little to do with how the clutch acts, other than how if feels to you when it shifts. Thicker or thinner has no great impact on the clutch action when at running temps.

ATF works well, and has been a proven winner in 2T cases. ATF's will normally be around a 20wt. viscosity.

Oils with friction modifiers meet the API SL/SM standards. Motorcycle oils meet SF/SG or SJ standards. It's marked on the bottle.

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Oils do NOT have to contain the dreaded motorcycle clutch killing friction modifiers, that are always warned against, to carry the API SM certification. In fact, there are few oils that you could find that would actually contain anything that would be detrimental to the clutch action. Sure, one oil may feel different when shifting than another, but most oils on the shelf simply do not ruin clutches.
Besides, most all oils will contain "friction modifiers"...even the ones that state they do not.
You may say, "that's false advertizing"...and you would be somewhat correct. Many oil peddlers will state many things that just skirt the truth and the real issue just enough to have you believe something that is a moot point to begin with. Whatever it takes to get you to purchase a $12 qt of oil instead of one that costs $2.
This tactic would include relying on consumers, who pass around track myth and dealerspeak BS on a frequent basis, to get their misinformation message out to the public.

There is little to be said about an oil that is API SG/SJ rated, other than most of the moto specific oils you see today are still SG rated. Which means that they carry a certification that has been discontinued completely. It is (was) only good for autos from 1993 and earlier.
The oils of today that carry the API SM certification are far better oils than the SG oils of old. Oils that also carry the ILSAC GF-4 certification are even better oils....wait let me rephrase that..GF-4 oils have gone through alot of testing that includes drive train and gear wear, whereas the SG rated oils have gone through basically zilcho as far as testing is concerned.
Some testing criteria is a bit more stringent than others, and the API certifications do not give us much at all as far as performance testing, and the JASO standards for motorcycle oils give us even less assurance of performance quality, other than they have gone through a frictional charactoristics test.
(which many oils on the shelf could also pass...even those with the dreaded "Energy Conserving" certification)

Motorcycle specific oils may or may not be good oils. There is very little to depend on when it comes to the JASO certifications. Sure, there are some JASO certified moto specific oils that are top notch oils with heavily fortified additive packages, but there are also $2 "car" oils on the shelf that are every bit as robust and will do just as good of job, if not better, than an oil with a bike on the label.

Get your clutch fixed and change your oil often.
(and try to be a little bit more discerning of what is truely wisdom, and what is track myth BS)

76GMC1500 said:

An 80w oil, hypoid or not, would be significantly thicker than ATF which I believe measures in somewhere around a 7w. As for the difference between a 10w30 and a 10w40, it's unlikely you'll notice much of a difference as they are both a 10w oil. The first number, the viscosity, is measured at 100 degrees C. So, a 10w30 and a 10w40 at 100 degrees C are both going to have the same viscosity. As the temperature increases, the viscosity of the 10w40 will decrease less per unit of temperature increase. However, since most of our 2-stroke transmissions spend most of their life pretty close to 100 degrees C, a 10w30 and a 10w40 will have roughly the same viscosity during normal operating conditions.

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No, thats not correct. Gear oil and motor oil use different viscosity scales. 80W gear oil is thin almost like ATF, but probably closer to a 5W30 motor oil (75W gear oil seems just like ATF). 80 W Hypoid gear oil (designed for differentials) IS very thick.

I have seen people get the Bel-Ray Hypoid oil by mistake and it will make the tranny not work well.

So is it really safe to use ATF that gets changed after every ride in a 2t crankcase? :think:

you know what it is safe I have a very reputable source that will remain my secret. But i am going to use super-tec which is available at your local wal-mart. :)

ATF is fine to use. TypeF ATF is probably the best choice, as it has been designed so that the frictional charactoristics are suited for the high revving, clutch feathering style of riding that a small bore 2T demands.
It also is very inexpensive.

I can almost guarantee that a rider who changes out $1 ATF in a 2T box every ride, will be far better off than the rider who buys $12 moto specific "synthetic" oil and runs it for many hours (let's assume 12 hours) of hard riding.
(KTM recommends 15 hrs of riding before changing oil...bad recommendation IMO, but it is in black and white)

hot125mod said:

So is it really safe to use ATF that gets changed after every ride in a 2t crankcase? :think:

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If changed frequently; and based on the normal life expectancy of a dirt bike engine (in hours) its safe.

It was popular in the 70's when trannys were notchy and it does let the clutch bite better.

However I stick to Bel-Ray 80W Gear saver (bought in case its not that expensive) since the 1980's.

hot125mod said:

So is it really safe to use ATF that gets changed after every ride in a 2t crankcase? :think:

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I run it in the transmission of my 1982 Maico 490.

The transmission in that thing is worth about as much as a two year old 125, i.e. Maico parts aren't cheap.

If I had any reservations about its performance, it wouldn't be in there.