what transmission oil do you use

[paul]

what do you recomed (aircooled 2 stroke)

[firko]

ATF

[geraldo]

ATF is fine if you have an automatic transmission in your VMX bike ,otherwise I suggest a dedicated motorcycle gearbox oil like belray gearsaver sae 80w, these oils are specifically designed to cope with the wet clutch , high load and gear meshing of a motorcycle gearbox

[KB171]

ATF   g/box,forks and shocks,

[huskyrider78]

Belray Gearsaver

[Freakshow]

any oil for boxes, ATF is known to scrub out bearings etc. may as well use water to lubricate,  it just creates a space between the metal.

Pulled apart a DT1 recently with that weird stinky red liquid in it and sure enough it looked dry and scrappy in there and the guy said it was rebuilt last season.   The whole thing about viscous power savings by ATF is wank, try losing 2 kg and you'll go faster .

And id be staying off that synth gear also.    Just use normal run of the mill oil out the ground , like it was made to use and youll be doing yourself and your bike the world of good even at 10w youll never wear it out

UNless you plan on running a land speed record or somthing and need some low drag on your 2 stroke tranny whats the point and even then the LSR boys would laugh it off.

[geraldo]

err ,ATF stands for automatic transmission fluid ,and I'm sure it does a great job when used in that application ,BUT why would you use it in a manual gearbox (there are proper gearbox oils avail) ,forks (there are proper fork oils available) or shocks ( there are proper shock  oils available)
maybe I have it wrong and you use ATF for all applications - as 2 stroke mix ,as chain lube , as air filter oil , as sex lube , etc etc

[mike1948]

Just plain old monograde oil.  Changed each meeting.

[BETRIC]

CASTROL MTX GEAR BOX OIL MADE FOR 2 STROKE GEAR BOXES, I RUN IT IN ALL MY COOPERS & YAMAHA'S WITHOUT A PROBLEM.

[Mick22]

This topic always makes me laugh because we all become experts on oil based on what we think they do

I will give the benefit of doubt in case there are any chemical engineers on here that have offered advice.

If you want to know what oil to use and you want an informed answer, ring any oil company ask to speak to there "tech dept"  about a motorsports application and ask away, definitely don't speak to their sales or retail people. I have done this plenty of times and they have been more than helpful and have given detailed answers about what to use and why.

Just out of interest, I once called castrol about a road race bike I was running a few years back and asked what was the best gearbox oil to run....they recomended ATF not their own MTX. It was called ATF DB (i think that was for Daimler Benz) and had lots of EP additives etc, I never had any problems with it. I have heard stories about ATF causing bearing & gear face probs but I think its an old wives tail as Auto gearboxes still have bearings and gears after all.

But like I said, don't take my advice ask the real experts

[brent j]

My 2 cents worth, or maybe 1.5 cents the way the world is going.

The last two stroke I ran was a TY250 and I tried 80/90 gear oil, ATF and TORCO manual transmission fluid.

The gear oil made for tight gear changes until it warmed up then it was fine.

The TORCO was the same but the clutch felt better, much more positive.

ATF seemed fine.

ATF is meant to lubricate gears and bearings as both exist inside an auto trans. It is also designed to provide drive to wet plate clutches.

The TORCO is a 40wt oil and designed to provide drive to wet clutches as well.

I used ATF in LENCO transmissions in a drag car and found we had to adjust the clutch pack every run and replace bearings every year. When we changed to TORCO we would adjust the clutches every other meeting and run the bearings for two + seasons. The oil also stayed cleaner for longer.
The TORCO oil gave a more positive drive and produced less wear in the clutch packs. The engagement of the clutches was also smoother.

I noticed the same result on the TY even with slightly less horsepower

I'm currently building up two TM125's and intend to run TORCO MTF in both

Cheers

Brent

[firko]

I've been using ATF in my Maico square barrels transmission for 38 years and have never had any transmission or clutch problems (except for a non oil related clutch problem at the Nepean pre 75 meet). I've used in all of my other bikes as well except for CZs which need a heavier oil,  and I've had zero problems. It works for me.

[YSS]

dito

[mx250]

On race bikes I use Mobil 1, or another full synthetic, and run half full . Old Proddy racers trick. On an RGV at Eastern Creek it is worth 2 KPH (+plus the draft is worth an overtake opportunity) down the main straight.

No probs .

On a resto or everyday bike where the ultimate performance is not required, just a good quality engine oil as recommended (synthetic perferred by me). The Specalist oils might give better performance and protection but the gearbox is not a high wear item. Smooth gesar changes will do more to save the gearbox rather than the oil.

It is the 'shearing' action of the whirring gears and the comtamination from clutch material that does the most damage. What ever oil you use get around this prob by changing your oil regularly. Oil is cheap insurance  .

[vandy010]

after a lengthy discussion with a bloke thats worked in an "oil sampling laboritory" for years,
i now use good old off the shelf at K~Mart "Valvoline"
no probs!