Final drive oil

[rocketbill]

Changed my final drive oil today and then noticed it should be fully synthetic. I have been using kawasaki 80w-90 mc gear oil. Changed it when I bought this bike 3k miles ago. Should I go buy the synthetic? Should be 75w-90 I figured 80w-90 was close enough but it was not synthetic. I changed it after one year because when I changed it last year it was dark like motor oil, when I change my final drive oil on my Yamaha fjr 1300 it looks almost like new oil.

 

[TURBO200R4]

You are not going to find the answer in the books
So here is what I would do if the bike was mine
Mine was black at 6000.
I started to change mine at 5000 miles
and also change motor oil at the same time. The final drive takes very little oil so buy the synthetic oil.
I would leave the regular lube in there and ride it for 1 or 2000 just enough to clean it some then go with the synthetic lube.
Just be very careful and don't snap the drain bolt/magnet off. It is very easy to do.
Hth

 

[rocketbill]

That sounds reasonable. Will not put many miles on this winter and then I will change with synthetic this spring.

 

[rocketbill]

Found this at the local Yamaha shop.

 

[rckt3]

Changed my final drive oil today and then noticed it should be fully synthetic. I have been using kawasaki 80w-90 mc gear oil. Changed it when I bought this bike 3k miles ago. Should I go buy the synthetic? Should be 75w-90 I figured 80w-90 was close enough but it was not synthetic. I changed it after one year because when I changed it last year it was dark like motor oil, when I change my final drive oil on my Yamaha fjr 1300 it looks almost like new oil.

I change the final drive oil every time I change the engine oil, which is once a year, for the amount of oil it takes and the time it takes, why not?

 

[Journeyman]

Having replace one FD and rebuilt another on my Roadster ($$$) I would not take any chances with different weights or non-synthetics. @TURBO200R4 's advice is good (as always) to run what you have a little as a cleaner, then put in the right stuff. I always used the 75-90 Mobil 1 gear oil you can get at auto parts stores and change often. Be sure to lube those splines every other change with moly

 

[rckt3]

I use motul, both are excellent products