Amsoil severe gear
Elite HDF Member
Joined: Dec 2007
Posts: 4,271
Likes: 29
From: Green Country,Oklahoma
I have posted on this a couple of times due to problems I was having and quite sure others were also.I drank the Koolaide on synthetic oil in trans also.Took it out and will never put it in again.Don't care what type it is.
Tourer
Joined: Oct 2007
Posts: 367
Likes: 5
From: Draper, Utah
60K on my 07 RG I've used Amsoil 75-140 in the tranny since the break in and it's worked fine for me. Every bike is different I have never had the infamous 5th gear whine in my bike and all Harleys clunck when you put them in gear "it's a Harley". Amsoil isn't for everyone but it works for me.
Road Master
Joined: Mar 2010
Posts: 934
Likes: 54
From: SE Wisconsin
just an FYI:
for the guys that want to run a heavier oil in their tranny, there is a big misconception on oil viscositys out there.
First of all, motor oil and gear oil weights are measured on different scales. With that said, a 75-90 gear oil is actually about the same in viscosity as a 10w-40 motor oil. So a 20w-50 is thicker than the 75-90 gear oil, and a strait weight 50 motor oil is thicker yet.
If you are looking for a good heavy oil to quiet down the tranny consider a strait 60 weight motor oil.
Amsoil just introduced MCS 60 for exactly that purpose, ask your Amsoil dealer about it. And no, I'm not a dealer, just did some reasearch on it.
keep on ridin..
for the guys that want to run a heavier oil in their tranny, there is a big misconception on oil viscositys out there.
First of all, motor oil and gear oil weights are measured on different scales. With that said, a 75-90 gear oil is actually about the same in viscosity as a 10w-40 motor oil. So a 20w-50 is thicker than the 75-90 gear oil, and a strait weight 50 motor oil is thicker yet.
If you are looking for a good heavy oil to quiet down the tranny consider a strait 60 weight motor oil.
Amsoil just introduced MCS 60 for exactly that purpose, ask your Amsoil dealer about it. And no, I'm not a dealer, just did some reasearch on it.
keep on ridin..
Ultimate HDF Member
Joined: Jun 2009
Posts: 6,932
Likes: 4
From: 46th State, USA
I've been using Amsoil 20W50 in all 3 holes. I'm changing the transmission to Amsoil Severe Gear 75W90 to make it run a bit more quiet.
Those of you that have changed to Amsoil Severe Gear and experience an odd discoloration may be seeing a mixture of some left over gear lube from the previous brand.
What's really strange, is using the same identical Amsoil gear lube in the same brand Harley engine by several different rider/owners and getting different results. You would think everyone would be getting the same results.
Hummm! Amsoil must not know what they're doing. Yeap! That's got to be the answer.
Those of you that have changed to Amsoil Severe Gear and experience an odd discoloration may be seeing a mixture of some left over gear lube from the previous brand.
What's really strange, is using the same identical Amsoil gear lube in the same brand Harley engine by several different rider/owners and getting different results. You would think everyone would be getting the same results.
Hummm! Amsoil must not know what they're doing. Yeap! That's got to be the answer.
there ya go.
As I said, for me, the clunk is still there, and when hot...just as hard to find neutral. (Amsoil Severe Gear 75W90)
Here again, with the massive gears, loose tolerances and such of the hogs, there could be a range of difference from one bike to the next; I would think not so much in the engine itself though, where tolerances are more important.
Another factor is the way it's broken in and on what oil. That would account for a lot of difference one bike to the next.
As I said, for me, the clunk is still there, and when hot...just as hard to find neutral. (Amsoil Severe Gear 75W90)
Here again, with the massive gears, loose tolerances and such of the hogs, there could be a range of difference from one bike to the next; I would think not so much in the engine itself though, where tolerances are more important.
Another factor is the way it's broken in and on what oil. That would account for a lot of difference one bike to the next.
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Road Master
Joined: Mar 2010
Posts: 934
Likes: 54
From: SE Wisconsin
Good point on the recommended oil and the 20/50 equivlant.
I'm not sure we are really talking about the recommended oil so much as running something a little "heavier" though. And by "heavier" we mean heavier than the recommened oil. Amsoil Severe Gear in this case.
The big point I am trying to make here is the 75/90 Severe gear lube is actually thinner than the 20/50 motor oil. Please be aware, the higher numbers on the gear lube are misleading. Some people are doing the exact opposite of what they want as a result.
Since the transmission is basically gears submerged in oil, many don't see a problem with going a little heavier. And, the answer is not what it might seem. For the Amsoil guys, the strait 50 or 60 weight is worth a look in this case.
It would be a good question for the Amsoil tech as to why the 60 isn't recommended for TC's or Evo's - I'D sure like to know what is missing from it. Shear factor? Doubt that. Flash point? Irrelevant. Metals? Or what?