Switching my YZ to ATF?

[04whyzee]

I've decided to make the switch to ATF in my transmission to see if I can make my gearbox shift a little smoother. It has always been rather "notchy" for lack of a better word and is reluctant to go into first gear from second while I am rolling. I almost have to come to a complete stop in order to shift it out of 2nd into 1st without getting stuck in neutral. Like when I'm charging hard into the inside line and I know 2nd just won't have enough power so I try to downshift to first while braking it just doesn't want to do it. Yesterday at the track I probably hit neutral 3 or 4 times on accident and almost fell over because I lost all my momentum when I revved it up and let the clutch rip. Do you think switching to ATF will help this out any? Forgot to mention my bike is an 04 YZ125. I have seen a few posts that say I can use ATF in my bike but I want to know if I need to flush the gearbox with ATF first and then fill it up or just drain the old oil out and pour in some fresh ATF? If anyone can help me I would greatly appreciate it.

[Thump_This]

switch to ATF Type F without friction modifiers. also do the mod to notch the teeth off. you should be fine then. i dont have a link to the article but someone might be able to help and chime in.

[FFRacing11x]

I recommend using one of the synthetic trans oils from Silkolene, Belray, etc. They are designed for your trans and clutch.

[paul reed]

it said here it was fine huh?...that`s a laugh...lotsa armchair engineers here...something to consider is shear strength...read up on the subject yourself...i`d recommend considering getting your info from engineers manuals...not some guy reading tv guide...sure,some have run it and seem to have had no problems...that doesn`t mean it works better...or even that`s it`s suitable for that application...from the information that i`ve read,it`s not suitable...and i posted as such...i`d suggest looking into your inner shifting mechanism...sometimes polishing certain areas can be rewarding...sometimes things get bent...and wear can take it`s toll...if you change your oil often,it helps...magnetic drainplugs are real nice

[04whyzee]

OK fine but DO I NEED TO FLUSH THE GEARBOX WITH ATF BEFORE I SWITCH OVER? Thanks for the help so far.

Paul the bike has always shifted like this since it was brand new so I'm led to believe it is the nature of the beast. I have tried Yamalube 10w-30 and Silkolen 10w-30. The Silkolene seemed to shift a little smoother but still not where I want it. I want my 88's gearbox back. That thing was smoother than crunchy peanut butter.

[yzernie]

No, fill it and go.

[paul reed]

good call Tryce...my point is simple...the folks who design these oils and fluids know what they`re doing...Joe Armchair prolly wouldn`t score very high on the exam given to prospective engineers at hiring time at the manufacturers offices...this ATF buissness in the gearbox is an old subject...over 20 years old...ATF is designed for auto trannies and if ya really wanna learn something-run gear oil in your automatic tranny...

[FFRacing11x]

No need to flush with ATF before you put in the BelRay or Silkolene. Save the ATF for your car, which it was designed for. ATF was not designed for the your MC just like the translube wasn't designed for your car.
Didn't somebody just say that?:
LOL Paul!

[ossagp]

Lol,,,Lots of advice about engineers,,,first ATF probably wont fix your problem,,sounds like you have something bent.

On ATF,,,,it's been used and used lots. I am not an engineer but may know more about oils than you have read here. I have been trained in failure analysis and have done field work for oil companies and bearing manufacturers. I use ATF in everything from my yz125 to my CR 500. The 500 is an 87 and is on the original gears. Regularly changed ATF will not hurt your transmission in my opinion, and that opinion is pretty well backed up.

Of course using real transmission oil that is "designed" as some are fond of saying with little notion of how an oil is designed, wont hurt it either.

Pauls' mother spilled ATF on him when he was little and scared him badly!!! lol.

Seriously,,,if you are in doubt, dont use it. Funny how so many standard transmissions for cars now call for it though, isnt it??? Kind of odd that companies like Caterpillar used and still use an almost identical formulation for years on their transmissions and drive units isnt it? And someone is going to tell me that it wont hold up in my motorcycle????


But I doubt it will fix something that is bent, broken, or has a defect from the factory.

[FFRacing11x]

No Andy I am not a chemist or engineer...but I would wager to say that I have rebuilt more 2 stroke bottom ends than just about anyone here. So I am basically speaking from not only mechanical experience, but actual time using and testing with just about every lubricant available to the M/C racing public.
In my opinion, the "designer" lubes will usually offer better results than those that are not use specific.
Will ATF work? Of course it will as you stated. Does it work as well as the use specific lubes. IMO no. Just the fact that ATF will not last as long as the specific lubes tells me that it isn't up to the task. You said "regularly changed".
As I said, I can't give you scientific affirmation on why I choose to run what I do, except that my experience tells me I made the right choice.
I suppose just about anything would work, including banana peels, just how well it works is something else.
JMO

[paul reed]

it wasn`t that which scared me...it was an engineers write up on this very subject that i read and still might just have in my posession that made me think it wasn`t such a great idea...i take all info with a grain of salt...and look into things for myself...these days misinformation and planned obsolescence are practiced to the 9`s...i personnally make no claims to be a petrochemical engineer or a fluid dynamics professor...and like i said,most armchair joes wouldn`t pass the exam...i have read much on fluids,oils,solvents,lubricants and fuels and i was taught to pay heed to what schooled engineers say-i might not allways agree-but i do listen...i grew up looking at all the failed trannys and gearboxes and i`ve came to know that the trannys just got worse-not better!...they quit makin all the forged crankshafts in chevy smallblocks for a reason-they lasted too long...should we assume Caterpillar is trying to make their products last forever and don`t wanna play the planned obsolescence game...nowadays,some manufacturers employ robots to get an acceptable lifespan...but they try not to exceed planned service life when designing certain parts...as far as engineers reports being accurate-and misinformation...look no further than the Marine`s new verticle takeoff aircraft...ossagp-what made you switch to it so long ago?...was it an armchair joe or an engineers report?...i didn`t say it would hurt anything-but i will say now " i seriously doubt it is the optimal performing fluid in this case"...i mentioned ATF`s shear strength might not be adequate...i have ATF in 55 gallon drums-yet i buy gear oil-i also have more than a notion of the many variables and constraints considered in the manufacturing of oils and lubricants...including those used in machinery used to produce foods for human consumption-LOL...thought i`d share this with you...prior to 1980,20W-50 was generally recommended oil by auto manfacturers for temps above 40 degrees F...that didn`t last long...soon,General Motors and others were recommending 5W-30 for summer and 10W-30 for winter and dropped any recommendation of the 20W-50 at all-haha-those that weren`t paying attention might have had a little less engine life expectancy...that was pointed out in material written back in the day by Don Johnson,VP Product Engineering,Pennzoil Products Co...ya know that guys full of it too!...he works for an oil company and he`s got that E word in his job title!...

[FFRacing11x]

Mr Reed, how come your avatar is the color of ATF??

[yzernie]

I guess the bottom line here he wants to use ATF. It's his choice.

[KX02]

I never heard of using bananas, but isn't saw dust supposed to work really good in transmissions?

[paul reed]

that red color in the ATF is a dye that changes color when fluid temperatures exceed the engineers suggested operating temps...it`s not enough to just smell the burnt fluid...Psyklone hooked me up with the avatar...looks like a clown design...he`s gonna give me roost and flames soon...i gotta keep up with Woodyyzf and frakke...i just looked at the performance specs on Amsoil ATF versus one of their better gearlubes...Amsoil claims their ATF is far superior to other ATF`s available....in the four ball test ASTM D4172 ...the synthetic gearlube showed same wear specs in test results-but the gearlube was tested at a much higher temperature,at a higher rpm...it would be interesting to see how "average ATF" stacks up when compared...one look at the price and i can see it must be special...i also just read an opinion about ATF not being as good as motor oil in steering gearboxes...this was the opinion of RH Shepphard who claims to notice quite a difference when it comes to wear on the gears in the steering box`s he`s been rebuilding for the last 15 years...i hate argueing with such nice guys as ossagp,but the comment about guys with little notion about how oil is concocted really got me going-that same subject has been on the internet for years now...can`t he just admit we`re allways right about stuff!...LOL!...well,he even said he was a bearing failure expert!...

[paul reed]

kx02,i seen lotsa sawdust added as well...when buying stuff,it`s allways best to drain the item in question and take a look at the goop that comes out...the look on some guys face can be priceless...works well?...not around here it don`t!...as far as i know-the bananas were more common in the early days of ripping people off...and yes,the ground up peels worked better that the part we don`t eat of the banana;D

[Yardpro393]

Originally posted by paul reed
it said here it was fine huh?...that`s a laugh...lotsa armchair engineers here...something to consider is shear strength...read up on the subject yourself...i`d recommend considering getting your info from engineers manuals...not some guy reading tv guide...sure,some have run it and seem to have had no problems...that doesn`t mean it works better...or even that`s it`s suitable for that application...from the information that i`ve read,it`s not suitable...and i posted as such...i`d suggest looking into your inner shifting mechanism...sometimes polishing certain areas can be rewarding...sometimes things get bent...and wear can take it`s toll...if you change your oil often,it helps...magnetic drainplugs are real nice

pual you obviously have never been into an automatic transmission. They use the same materials for thier friction and steel plates , bands and drums as bikes do. as a matter of fact the same companies make the plates for both autos and bikes. the planetary gears are under much more of a load than your bike will ever see. the suburban towing the 35 foot motorhome will see much more extreme operating conditions that your bike ever will. gear saver is nothing more than slightly higher viscosity Transmission oil.

also McGrath's mechanic was the one that started touting the benefits of running ATF in your bike. since then (back in 98) I have found that alot of top mechanics use it as well.

I have used it exclusively in my bikes since 98 with no problems. My clutches were lasting 18 months to two years!!!!

before i sold my 99 cr 250 i blueprinted my motor. i rode that bike at least 5 hrs per week for 3 years, almost every weekend. I am a really heavy rider, and ride in conditions from sand to clay. I am hard on transmissions.

What i found when i mic'ed all the transmission shaft's od's and the gears id's, etc. were that there was no measureable wear at all. they were all in the low end of the tolerances. i had no notches in my clutch baskets, all my trans, bearings had NO freeplay (measured with dial indicator), and the runout on all the shafts were perfect.

Don't be so quick to insult sourced of information unless you have your facts straight. That's a knee jerk reaction.

[ossagp]

Ok, lol,,, just in from TV guide.

Seriously, starting with color breakdown of ATF. I bet Paul and Tryce have never seen the color change on their preferred transmission oils, have you? Stays the same forever right?

I have tried lots of lubes, and have seen none that worked any better than often change ATF. Of course I was TV guide directed to try it in the first place. Wouldnt do a thing without consulting that you know. The first place you look for how your oil is doing on your gears is the crankshaft primary gear. Go to top dead center and then rotate 12-14 degrees, now mark the spot the gears come together. Now pull your primary gear or clutch basket and look at the crank gear. If you are going to have premature wear, that is where it will show up, that gear gets the hardest hit at that point everytime.

Lol,,,talking to engineers is something I have done all my life. Having been raised by and around them. Better yet listen to one engineer talk to another! Never mind what they tell you.

Now, for those of you who like to throw the same word "engineeer" out, consider this: The transmission was designed by just such people. Then the company prints a manual that usually says to use motoroil. (Still with me "engineering groupies"?) Now, that tells me that they dont think that your motorcycle transmission needs any of the gear oil specific requirments that I have seen quoted here. Oils with hypoidlike qualities have their place of couse and maybe they do work in bike transmissions better than mine. I just think it is curious that the manufacturer's engineers don't scream to use them.

Anyway, all is good and anyone here can argue with me anytime they like. It is really what I come here for.

But I am going to do just like "Yard" and keep using what works for me. You see, I am not just comparing what I think has caused some sort of malady in an engine I am doing for someone else, or an engine that is going to see a season with me. I have several such as my CR500 that has been working for me for nearly 17 years (some longer even).

Has the sky fallen yet?(If enough of us use the dreaded ATF, it just might!!)

[ossagp]

Paul,

Get to your man Sheppard on this if you want, a steering box spends most of its running time with the same gear teeth meshed at the same point. Motoroil stays put better and therefore provides a better cushion.

[paul reed]

yardpro...i slaved at my families tranny shop for many years...i`m pretty sure i`ve seen the insides of more damaged units than the average human will see in a many lifetimes...the clutchpack is only 1 consideration-i have no problems there-but on gear faces,ATF just plain isn`t as good...and i do beleive a cr500 is more comparable to a formula 1 racecar than a Suburban...compare the weight vs horsepower ratio...i`ve used the nasty ATF fluid in a bike that i`ve bought that way,i won`t be using it again...the 4 ball test i mentioned gave same scrape diameter but the rpm`s were higher and temps were higher for the test of the gear lube...it sure looks to me like even expensive latest design ATF is still not the optimal thing to put in the hole...so i won`t and never will and you guys can`t make me-so there...and Jeremy uses plastic gears in his supercross bike-yes,his bike has nothing to do with mine...and he prolly doesn`t care if his bike lasts more than 1 season-it also gets torn down often...what`s McGrath got to do with this anyways?...maybe you guys can enlighten me on the advantages of using ATF...???...i haven`t heard one yet...i`ve only checked into using ATF further and found it less than optimal when compared to gear lube...especially when thermal breakdown is involved...so why are ya whippin a dead horse here?...LOL...please don`t bother telling me it`s cheaper...cause if i looked up the specs on the cheap one it would prolly really look sad,it sure wouldn`t seem to be optimal...i`m not here to argue,i`m here to set the record straight...LOL...anyways,i`m sure tests with a spectrometer would show more particles suspended in ATF...particles that are supposed to be on the gears...