Gearbox oil.

[wa1udg]

What are you guys using for gearbox oil.  I have Redline 75/90 gear oil in mine but it's time for a change and Mobil One has a gear oil on Amazon I can get shipped free.  I know this opens the BMW clunky shift worm can, but WTH, it's important, the trannies aren't cheap.  

[montmil]

BMW recommends an 80W90 GL-5 gear oil. As far as brand preference, I've been using Castrol but others are as good.

Is the Mobil 1 gear oil a synthetic? Or is a syn gear oil even available? Free shipping and no sales tax is always a good thing. [smiley=thumbup.gif]

Some Airheads have switched to a synthetic engine oil and discovered new drips. After switching back to dino oil, the drizzles went away.

Monte

[Bob_Roller]

I've been using the BMW branded gear oil, it's made by Spectro Oils .

I'm not an enthusiast of full synthetic lubricants in an airhead bike .

I used Mobil 1 motorcycle oil in the '81 R65 and it leaked within a few months, replaced the leaking rear main seal, it started leaking again in less than a month .

Went back to the Spectro Oil that I had been using for about 20 years and the rear main seal leak stopped in less than 50 miles .

This is just one persons experience, others have used synthetic oils with no problems .

[Semper Gumby]

WooHoo an ADOT!!!

Valvoline in the Dark Blue Bottle 80W90 from October through April -- 85W140 during the hot months.  So I change the final drive/drive shaft/tranny out twice a year (which is the really important thing).  My choice of oils is entirely subjective in that it feels (shifts) good and I can get it at Autozone at a reasonable price.

The dark blue bottle is a Blended Semi Synthetic oil.  I tried the BMW 75W140.  It felt like water in my gearbox and later that night leaked a nice clean 14" wide puddle on the floor below the shifter seal.  Although 1980 is the change over year for synthetic compliant seals, the seals in my 03/1980 were not compliant yet.

I hear that Redline is an excellent oil.  Since I can't get it at ANY Autozone in the country it is not on my approved list of oils for going on "walkabout".

At the moment I have all Valvoline/Autozone products in my R65.  The original tranny is at 105,680 miles an counting on a bike I have owned since 1993.  I'm the second owner.

Your results may vary.  

[wa1udg]

Yes the Mobile One is a synthetic.  I have had Red Line products in my 82 for about 10 years with no leaks, but it only has 4500 miles on it.  Used Castrol 5W50 in the engine for several years. Boy does it crank in cold weather.   Right now it just worked out (son raided my stash of 20-50 Castrol for HIS bike) that I have about a 50/50 mix of dino and synthetic Castrol 20/50 in it.  Seems  good, but no  cold weather test.  Red Line makes a "standard" synthetic gear oil  and a special "high shock" gear oil for use in devices which get shock loading.  That's what I have in the gearbox.  Always had trouble getting 800 ml into the thing without tilting it a bit.   Don't want to overfill.  Apparently according to some sources, ya can't change it TOO often.