Gear oil question

[hikermikem]

Maybe a stupid question, but I've not seen it kicked about here. My '82 GS1100G calls for SAE 90 hypoid oil for the gears. I see the local Wal-mart sells a synthetic SAE 80-140 hypoid gear oil.

Is the 80-140 range a better alternative than straight 90 weight??
Is synthetic gear oli even a good choice??

I'm going to change out the oil, & grease the rear wheel spline (with the Honda moly-grease) sometime soon - is there any other maintenace stuff I should do for the gears & transmission?

After my bike gets warm, it kinda clunks into gear & the gear selector foot lever sounds "clicky." Perfectly firm when cold. Is there something I can adjust somewhere to take up any play? Note, bike has approx. 30K on it, don't know much about the first 26K.

Looking for opinions, thanks.

Mike

[focus frenzy]

thats to thick, go with the 75W-90. the W is winter so it flows like 75 weight oil cold but flows like 90 warmed up. 140 is THICK!

synthetic is the way to go if you are willing to spend the extra cash as it is slicker and holds up to the shear loads much better than conventional.

the differance is big enough that synthetic is all we run in the transmissions and differentials on the trucks at work. if it is good for trucks it cant hurt a bike.

[BassCliff]

Hi Mr. hikermikem,

I also use the synthetic 75w-90 (Castrol) in my bezel gear case and the final drive unit. My transmission is a little "clunky" sometimes but if I do it right I can minimize it.


Thank you for your indulgence,

BassCliff

[psyguy]

just to clarify, your primary gears are actually lubricated by the engine oil
only the secondary and final gears are lubricated with the transmission oil
so, the noise you hear when shifting gears doesnt have to do with the transmission oil but the engine oil
runing 15-50 in the engine may help smooth shifting

[hikermikem]

thanks for the info guys - I understand about the transmission & gear differences. I will look for the 75W-90.

I use the blue bottled Rotella oil (5-40) in the engine. Perhaps i will try a thicker oil next time & see if it makes a difference.

Thanks

Mike

[RWhitehouse]

My 450 calls for 10-40 oil, and that seems to work just fine for shifting. I've heard people running 20-50 and getting some better shifting, but that might not be good for any cool weather riding.