I知 gonna be changing out my engine, primary and transmission fluids.......I know we can pretty much use the same oil for all three.... and it is sorta convenient but I知 considering using actual gear oil.....For my transmission. I hear it offers a quieter shift because of its heavier weight. Is it that noticeable?

 

I use SYNE in the motor and the primary.
For the trans I use Redline Shockproof......looks like Pepto-Bismo

 

I use Redline Shockproof, but have used automotive 75w-140 gear oil with good success. HD has a 85w-140 gear oil specifically for use in the primary and transmission under extreme weather condtions, both hot and cold. And yes, both have quieted the trans down some, and has made shifts smoother as well. I'd be comfortable using either, although having the red oil in the trans can come in handy in terms of identifying the where the oil is coming from if you have a leak.

Paul

 

I use Redline

 

Gear oil will make for a quieter, smoother shift. But you池e also right about the convenience of using the same oil in all three holes.

 

Adding sawdust really quietens things down, too.

Oil and Oil Related Topics

 

The major benefit of having three oil supplies is the ability to use the optimum lubricant for each purpose. Motor oil is not a good gear lubricant, gear oil may contain additives that are not good for wet clutches and so forth.

Just because you CAN use the same product in all three places doesn稚 mean it痴 the best idea. I use Syn 3 in the motor, Bel Ray gear oil in the transmission and Formula+ in the primary, but it痴 your bike, do what you want.

 

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Your all set.... Enjoy the ride! ______________

Many years back, the mother ship came out with SYN3. Was recommended in all three holes. Few years back, they made it a second choice with their Formula + non detergent gear oil for primary and transmission.

My guess is warranty claims.

From an engineering point, there is no filters, so high detergent engine oil has no business in there.

Getting two quarts of Formula is no problem. He convenience of one oil is nothing but what the mothership promoted.


They have a synthetic Formula + now but it's not necessary in a primary or transmission. And you would be doing nothing but testing their oil for them.

It does really nothing to quieten shifts. It's a huge multi disk clutch that plates tend to stick when cold, a huge spinning gear set in transmission with no syncs. Just square dogs that drop in to lock selected gear. (All actual gear teeth are always engaged)

It noisy and pretty crude. You want small chips and clutch junk to sink. Not stay mixed in detergent oil.



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We see countless posts about motor oil not being a good lube for gears..

But high powered Japanese motorcycles have used motor oil as gear lube for many decades.

And the Motor Company says it can be used.

I haven seen nor heard of a Harley gear wearing out prematurely unless the gearbox was run dry.

 

We live in a time no one makes the latest and greatest product. If some did the next company would copy it in days.
few facts:
20/50 engine oil and 80W140 gear lubes come out about the same in How thick they are. They use different test to rate them. If test the same they come out about even.
HD went to 80W140 in Primary because it protects better in low tems than F+ witch is a straight 50W and does better over all compared to 20/50. real world coin toss for most.
Engine oils with Zinc and friction modifiers protect best. That does not mean the others are not good enough. they use other additives to make up for the zinc and modifiers .
Do not use Lubes with friction modifiers in the primary They do not work well with the clutch.
20/50 SYN or standard oil fine in the primary ,long as it has no friction modifiers add.

Transmission is lubed by oil splashing around and dripping down. Good gear lube designed for it work well. Several great products mentioned.. Shock Proof heavy is a judgement call It is extremely thick Designed for racing and may not be the best option for the average street rider.
If you doubt that buy some leave it out on a cool night and pour it out. Ran Red line Shock Proof in a Touring bike. In colder weather It took a good amount of time for it to warn up and flow.
Many have use 20/50 sny oil in trans for years with no issues.
All comes down to what helps you sleep best at nigh.