Fluid Replacement
Road Master
Joined: May 2011
Posts: 1,070
Likes: 9
From: Auburn Ohio
Lots of Amsoil haters out there and as far as I'm concerned they are all talking out their ***! I've always had excellent results with Amsoil 20/50 in the motor. Combined with a HD oil filter and changed every 5000 miles it has always done everything I've asked of it and there are times when I ask a lot. My bike's normal operating temperature is about 230° and it has hit 300° more times than I care to remember and it has never been "black as tar" and/or "thin as water". When I drain it, it has never sparkled with metallic debris and there is very little shavings on the magnetic drain plug, if any. You guys can talk all the **** you want but Amsoil has made a believer out of me and has EARNED the right to be used in my bike.
Kind of ironic as both Amsoil and M1 recommend their 20w-50 motor oils in the transmission over their 75w-90/110 gear lubes. Whys that?
Road Master
Joined: Jun 2010
Posts: 1,221
Likes: 4
From: Annemasse (border of Geneva-Switzerland) facing Mt-Blanc.
Hi all,
After a few weeks running MOTUL 20W50 mineral oil in the primary transmission (meets HD spec.) and 75W80 in the gearbox, shifting is very accurate and the clutch is progressive but firm as it engages.
My only observation is that after a few days without using the bike, the clutch plates stick together as they did back in the 70's. It takes me 15 seconds to shake the bike back and forth to release the clutch but I guess that's the price to pay
After a few weeks running MOTUL 20W50 mineral oil in the primary transmission (meets HD spec.) and 75W80 in the gearbox, shifting is very accurate and the clutch is progressive but firm as it engages.
My only observation is that after a few days without using the bike, the clutch plates stick together as they did back in the 70's. It takes me 15 seconds to shake the bike back and forth to release the clutch but I guess that's the price to pay
Road Warrior
Joined: Oct 2006
Posts: 1,916
Likes: 0
From: San Antonio, Texas
its your money to throw away as you like....there are only really 3 types of oil..dino, synthetic and a mix of the two....under normal conditions (which all but the most highly modified harleys run) they all do a more than adequate job....none of them break down, run out of detergents or insufficiently lubricate under the conditons which a harley is used ....the higher grade oils are really only needed in extreme racing conditions ( I am talking about supercharging, track racing and the like)......they will all last for the 5000 miles or so between oil changes on a street bike...Oh, and those hot summer days when you are stuck in traffic for an hour doesn't count as "extreme", its just normal motorcycle use...
Road Warrior
Joined: Jul 2009
Posts: 1,979
Likes: 2
From: Northern Colorado
its your money to throw away as you like....there are only really 3 types of oil..dino, synthetic and a mix of the two....under normal conditions (which all but the most highly modified harleys run) they all do a more than adequate job....none of them break down, run out of detergents or insufficiently lubricate under the conditons which a harley is used ....the higher grade oils are really only needed in extreme racing conditions ( I am talking about supercharging, track racing and the like)......they will all last for the 5000 miles or so between oil changes on a street bike...Oh, and those hot summer days when you are stuck in traffic for an hour doesn't count as "extreme", its just normal motorcycle use...
Road Master
Joined: May 2008
Posts: 1,096
Likes: 107
From: Joplin, MO
Redline shockproof in the tranny, Redline primary oil in the primary and Mobil 1 in the engine for me.
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Cruiser
Joined: Oct 2009
Posts: 162
Likes: 0
From: Bremerton, WA
In the past year or so HD, as well as several oil manufacturers, have started recommending the use of their 20w-50 synthetic engine oil in more than just the engine. You can use it in the primary to lube the chain, and in the transmission, where it must operate in a gear-grindin' environment. So, how can HD say to use 20w-50 stuff where they once called for 75w-90 stuff? Wouldn't it be too thin to do the job?
Here's the answer: Viscosity is measured by different scales for engine oil and gear oil. The two systems aren't directly comparable, number-for-number. Here's a reasonably accurate comparison between the two systems. Please remember that I said "reasonably accurate", as there is some overlap.
SAE Engine Oil SAE Gear Oil
10w thru mid range of 20w = 75w
Mid 20w thru mid 30w = 80w
Mid 30w thru low 40w = 85w
Low 40w thru 50w = 90w
60w up = 140w
Outstanding HDF Member
Joined: Feb 2007
Posts: 2,710
Likes: 6
From: Spokane, WA.
I have used Amsoil, and M1 20-50. Right now I got Castrol 20-50 v-twin non synthetic in the engine, and it will do for my road trip this next week. I feel Ams, and M1 are both are pretty good. I have 1,400 miles on the bike at present. So, I got M1 20-50 on the shelf for oil change when I get back from my road trip next week.
Changing the engine oil, I do that more frequently than 5K, never usually even get to 3K before I change the oil. It's just me. I changed my oil on my flstf before 3K always, and used the scavenger oil change. ( peace of mind ) - see the web site below.
Will be doing a scavenge oil change on my RKC, so all of the oil gets changed as well. Even when you do a standard oil change the 28-30 oz of dirty oil remains in the sump. See web site below for more info.
http://www.roguechopper.com/about.htm
Changing the engine oil, I do that more frequently than 5K, never usually even get to 3K before I change the oil. It's just me. I changed my oil on my flstf before 3K always, and used the scavenger oil change. ( peace of mind ) - see the web site below.
Will be doing a scavenge oil change on my RKC, so all of the oil gets changed as well. Even when you do a standard oil change the 28-30 oz of dirty oil remains in the sump. See web site below for more info.
http://www.roguechopper.com/about.htm
Last edited by mgmmgm; Jul 29, 2011 at 09:04 AM.