Synthetic gear oil

[webbcraft2150]

Its time for gear lube change. Thinkin of going to synthetic, anything I should look out for? And... all the drain and fill plugs actually came loose!!! Gotta love antiseize!!

[TopCatGr58]

Hey Webbcraft,

The middle and final drives are isolated from the main engine oil, and so many have used synthetics in there with no problem at all. Just use the 80/90 hypoid type. AFAIK, they will mix okay with the residual left behind after draining, so I don't believe any special draining or cleaning technique is required.
T.C.

[graybird78]

hi. have used synthetics in my middle and final drive for 2 riding seasons now with no problems to report. i only service them once a year.as topcat said, it mixes with regular gear lube just fine.

[John]

I've been using syn gear oil for five years or so, with no problems at all.

[RS Thornton]

John,

Whose oil are you using?
Thanks

[remccool]

Bummer.... my list got longer ..... I completely forgot about changing the gear oil...... back to Auto Zone...... I would guess, based on everything I've found so far, IF there is any gear oil left in this bike, its probably from 1978, any ideas on how to get all the sludge out before putting in the new. I used 1/2 gallon of Kerosene to clean out the engine, still came out like syrup, very thick black syrup. I can only imagine what the gear oil is going to be like.

[webbcraft2150]

Remccool, you have two places to change. Check the threads on this. Before you go off getting stuff, you might want to make sure all the plugs will come out. These seem to weld themselves in after a while and can be a bugger to get loose. Also, there is a nifty dipstick for checking oil level (lost/misplaced mine). Not sure how you would check oil level without it. As far as cleaning things out, I have drained all the old goo out, replace the drain plugs, fill with something like Motor Flush, spin the wheel by hand a bunch of time, drain and repeat till you quit getting nasty stuff out. Refill with good stuff, replace plugs with a good dose on antisieze on them and ride.

[remccool]

Thanks for the info, I'll drain before I go to Auto Zone, and while there try to find some of that cleaner, and get the anti-c's (oops, that what we wore for radioactive stuff on the boat) I mean anti-seize.

[webbcraft2150]

There is a thread in the maintenance section with deminisons on the dipstick, looks easy to make. Before you drain, make sure the fill plugs will come out. You will be sad to have it all drained and find the fill plugs have welded themselves in!

[John]

Brake parts cleaner works very good in the drives. It mixes readily with the remaining oil, thinning it out. Put the bike in neutral, and spin the rear wheel for a while, making sure the cleaner has had a chance to do it's thing. Let it sit for a while, then drain the cleaner out, and leave it open to air dry, or do the cleaning again if the gunk is still thick when it drains out. Use pipe dope or teflon tape on the threads of the plugs, both the drain and fill plugs. That will prevent the oil from migrating past the threads and gathering road grime. Synthetic oil will do that. That's the only gripe I have with it. For fresh oil, I use Castrol synthetic gear oil. The book says to add ten ounces to each drive, but I have never been able to get my final drive to take anymore than eight ounces. I only change the gear oil once a year. I know, I know. Some of you are thinking "only once a year?" Think about it like this...How often do you change the oil in the differential of your car, if it even has one, or your truck. Once a year? Maybe not that often? How many miles is that? Do you put that many miles on your bike? Are the loads on the gears greater on the car or bike? Which one do you think would suffer oil breakdown first? The oil in the bike final drive or the one in the truck? Anyway, I don't feel that I need to change it every three thousand. That would be just a waste of oil, and time, and the synthetic is made for extended use anyway.

[webbcraft2150]

I change all the lube in my diffs, tranny and transfer case each year. That $900 diff overhaul many years ago still sticks in my head. In retrospect, I would say the small amount of gear lube in the 11's takes a bigger beating than the truck does, 'specially when it time to merge or the plugs need to be "blown out".

[jakeman]

These people have the little dipstick thing for about $2, course shipping is about $12.

http://yamaha.motogrid.com

[RS Thornton]

Oh C'mon.

For $1 go to the dollar store and buy a white plastic office wastebasket. Cut the T shape to the dimensions shown in the tech tips, mark high and low levels with permanent marker.
Cost is $1 and no shipping.

[DiverRay]

I use Red Line gear lube in all my vehicles. I've never had a problem with the middle or final drive, and I put on about 20K miles a year.( or more) I do change about once a year, the "sprine tune up".
The "dip stick" can be had from Yamaha, or it could as of last year.
John, you need to reread the book!! the middle takes about 4 oz. more than the final drive, if I remember correctly.
Ray

[John]

Ray

I just reread my manual, a Clymers, and it STILL says both the middle and final drive take 10 oz of oil, no matter how many times I read it. It is entirely possible that it is a misprint, but that is what it says. I use a 16 oz, glass, Pyrex brand of measuring cup to measure the oil, then I pour it back into an empty gear oil bottle to pour the oil into the drives. The final drive never takes it all, and I fill it right to the bottom of the fill hole, and rotate the wheel many times to make sure the oil migrates throughout the drive assembly. Synthetic pours very easily, but 80w90 needs to warmed like a baby bottle so it will flow easily.