Hi 

My Beta rev 3 200cc oil recommendation is 20w40, i have some gear oil sae 75w80 (10 liters) ...i have looked on the web to see if these fluids are similar but its all to confusing :] 

any reasons why i shouldn't use the sae 75w80

 

Cheers Neil   

The 75W80 will probably lubricate the gears and bearings OK but may cause clutch drag problems

Many thanks for the reply...can i assume that 75w80 ...is thicker than 20w40  which will cause clutch drag 

Cheers Neil

75W80 is what would be used in a manual transmission in a car and yes it has a higher viscosity than ideal for a Beta clutch and yes the viscosity is the problem.

There are easily available oils for trials bike gearboxes that give the best clutch action possible. Which one is the best is often the subject of discussion on these forums.

Gear oil and engine oils are rated differently. The end result is that a 75w80 gear oil is roughly equivalent to 10w40 engine oil. A lot of gear oil manufacturers publish engine oil equivalency ratings on the products. 

Thanks for the replys lads 

I will use the recomended oil ...just though i could use what i have in the garage first....got to be honest my clutch operation is silky smooth and wouldnt want to change that...ive only just had the bike so dont know what is in there the bike is a 2003 rev 3 200cc

FUCHS .....TITAN CYTRAC MAN SYNTH SAE 75W-80 Is the oil in question 

on the description it doesn't say the equivalent ...but does say "low viscosity"

neil 

ATF will come closer if you just want to use something cheap. I would not use the 75-80.

I know nothing about the specific oil he's got, but plenty of people run motorcycle gear oil of 75w or 75w80 in trials bikes. Silkolene Gear oil light, Maxima MTL, etc. All work very well in a variety of trials bikes. 

20 hours ago, snorky29 said:

FUCHS .....TITAN CYTRAC MAN SYNTH SAE 75W-80 Is the oil in question 

on the description it doesn't say the equivalent ...but does say "low viscosity"

neil 

Keep it for the car, you can do much better for your motorcycle.

https://www.fuchs.com/au/en/special/product/product/30190-titan-cytrac-man-synth-sae-75w-80/

Thats a little confusing ...why is it ok for a 8K car but not for a trials bike ?

Can i assume the issue would be possibly a dragging clutch....or it is just a cheap fully synthetic oil and will not protect engine/bearing wear 

To be honest, I haven't got a clue. I have always used motorcycle 2 stroke specific oils in my bikes. Please try that oil you have and report your findings, it won't do any damage I wouldn't think.

Good idea...i will give it a go and see

Don't forget, you don't change the oil, run it around the backyard for 10 minute and decide. Changing type of oil take '' sinking time '' to show it's quality.

Guy