Any of the above brands are fine but make sure it's gear oil.. 20W-50 in all 3 holes doesn't cut it with me.. If you're takin long trips on a bagger and only want to carry 1 blend for a backup that might be alright but you're NOT getting the proper lube for the job runnin motor oil in the gears.. I run the Spectro in my bike and use Mobil gear oil when I service my Brothers bikes..

 

Mobil 1 synthetic v twin is designed for wet clutch motorcycle uses. It does not have the friction modifiers that automotive use motor oils have that result in clutch slippage. It's all I've used for the last 4 bikes I've owned and haven't seen clutch slippage yet.

As far as gear oil vs motor oil in the tranny, next change I plan to try the Mobil 1 gear oil, but the folks who make it insist that the 20w-50 is better for this application. I change my transmission fluid at every oil change. Heck, it's a quart and an extra 5 minutes. I will say that it is a very noticeable improvement in smoothness, heat, and ability to find neutral over the Harley branded stuff.

 

changing gear oil isint really a must do every time you service your bike... the reasoning behind this statement, how often do you change the oil in your car gearbox and diff???. auto trans oil in the primary? no problem, Auto trans in your car has gears and a wet clutch pack like your bike no Difference. Engine oil? jap bike run their clutch in the same oil as their engine which needs regurlar changing from contamination , Harleys (SOME) separate engine oil supply Hence you don't need too change it so often. AS in most things people think on their bike it all must be changed yearly,,,BUT ask when the truck"S diff fluid was changed.. THE reply never its the same guys,, Short trips kills oil not long trips, look at your long haull trucks the milage they get from their trucks..

 

We did a pig roast a couple of weeks ago, and I took that opportunity to drain a little hog grease off the bottom of the roaster, and put it in all three holes. What could be better? Never ran as good before!

 

Just don't put dish water in it!

 

I agree. I use redline heavy shockproof. And at $16/quart I have to believe its good for more than 5k. I just got the bike this year so I changed it for my piece of mind even though th guy said he only had 2k since he changed it. But for the future I just plan on changing it 1 time in the spring.

 

Some synthetics are wrong for the primary but I changed to Amsoil 20/50 and my clutch grabs and sticks like a ****! Just sayin'.

 

The tranny is the one hole worth putting a synthetic in, IMO. Notice better shifting, regardless of brand, although I stick with a gear oil. 15-40W Rotella
(substitute any good HDEO) works the best in my primary, but I've heard good things about using an Automatic transmission fluid, like Dextron, there also.

 

for a Harley engine yes a 20/50w oil is what you need as the oil helps with cooling off the motor and prevents oil temp break down..
trans yes it has gears and **** but not the HEAT soak off a motor,,


A 10/20 w engine oil will be better as the 20/50 is too ****ing thick for your clutch pack, hence why the clutch played up

AUTO trans in primary or a light weight oil with no FRICTION MODIFYERS( clutch DEStroyers) additives

 

best bet is stick too one brand (TYPE) off oil , change too your new oil , do 500 miles, drop the oil again,and refill with your type used before,, THIS will flush your system out, especially going from engine oil too ATF trans oil. then replace say every 15,000 miles...LOOK at it this way some car makers recommend 50,000miles between trans services,,, BIKES are basically the same,,, mitibishi cars here in Australia don't service trans till 100,000 kilometers