Back to Conventional
Back to Conventional
I drained the Amsoil out of my 2007 Ultra today and replaced it with conventional. The difference is unbelievable. It doesn't even sound like the same motor. With the synthetic oil the motor made so much noise that it was embarrassing to crank it up around other people. Sometimes while riding it would clatter so much that I would roll out of the throttle for fear it would start spitting out parts. I know they say the Amsoil is top-of-the-line protection and after 2000 miles it was still slick as owl s#!t, but there is no way that kind of noise coming from a motor can be good.
Road Master
Joined: Mar 2009
Posts: 762
Likes: 1
Your situation sounds a lot like my experience with Amsoil and Mobile 1 Syn.(Also leaks developed...) I use 3 quarts Castrol GTX 20W/50 and 1 quart of Lucas Oil Stabilizer in my 02 Road King with gear drive. Sounds great, runs great and quit leaking. I change every 3k.
Road Warrior
Joined: Oct 2006
Posts: 1,916
Likes: 0
From: San Antonio, Texas
I went back to conventional because I had the same experience with synthetics in general: motor sounds like a ball bearing in a coffee can. Well, OK, not that bad but it was noticeably noisier. Don't care about the supposed "benefits" of synthetic. Noise can't be good. Runs smooth and quiet now - I use HD 360 (20w 50) and change every 5K as per the manual.
Road Master
Joined: Sep 2009
Posts: 787
Likes: 6
From: Charlotte NC
I also went to Amsoil and paid the premium because they all said it's the best. I could not stand hearing the engine noise it generated. I think the best thing about Amsoil is their marketing department! I have used Castrol Syntech synthetic for the last 5 years in my RK and just changed my new EGC over to it today. I don't hear any additional noise.
Grand HDF Member
Joined: Oct 2004
Posts: 3,829
Likes: 491
From: Northern WV
When I drain my synthetic oil out and fill with new (synthetic) oil, the engine is much quieter running.
JMO comparing engine noise between one with warm old oil that has lost some of its viscosity enhancers, to the same engine that cooled off and has room temperature, new oil (of any kind), will always give this result.
JMO comparing engine noise between one with warm old oil that has lost some of its viscosity enhancers, to the same engine that cooled off and has room temperature, new oil (of any kind), will always give this result.
Road Captain
Joined: Aug 2008
Posts: 528
Likes: 4
From: Alberta Canada
I'm starting to think the same thing, mine seems to clatter on cold starts sometimes...I might go back to Dyno oil and see if that helps...unless there's an additive I can find to quiet the thing down.
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When I drain my synthetic oil out and fill with new (synthetic) oil, the engine is much quieter running.
JMO comparing engine noise between one with warm old oil that has lost some of its viscosity enhancers, to the same engine that cooled off and has room temperature, new oil (of any kind), will always give this result.
JMO comparing engine noise between one with warm old oil that has lost some of its viscosity enhancers, to the same engine that cooled off and has room temperature, new oil (of any kind), will always give this result.
This was my second round with Amsoil. Changed to Amsoil at 5000 with K&N filter and used it again at 10,000 with H-D filter. Back to conventional at 12,000. It was always louder with the Amsoil, even when it was fresh.
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Road Master
Joined: May 2008
Posts: 1,065
Likes: 1
From: Madison, WI
I do agree that Amsoil makes more noise. I have heard it in three 2009 baggers. With all those great numbers in the tests...Why is that?
That stuff was killer in the V-Rod with the shared motor, clutch, and gearbox.
I really dislike Amsoil 20W-50 in the primary of the big twins. But I do like their Super Shift there.
That stuff was killer in the V-Rod with the shared motor, clutch, and gearbox.
I really dislike Amsoil 20W-50 in the primary of the big twins. But I do like their Super Shift there.
Road Captain
Joined: Sep 2005
Posts: 619
Likes: 0
From: Northeast U.S.
I'm running semi-synthetic now and have been dealing with low pressure on the gauge in high heat and a noisy motor like has been described. I am going back to Castrol 20-50 dino juice next change. See what happens.